陕西省种子植物新资料

报道了陕西省植物分布新记录2种1亚种。新记录种分别是梨序楼梯草(Elatostema ficoides Wedd.)和粉叶栒子(Cotoneaster glaucophyllus Franch.),新记录亚种是藤山柳原亚种[Clematoclethra scandens(Franch.)Maxim.subsp.scandens]。     

Miscellaneous taxonomic notes on Elatostema (Urticaceae) from China and its adjacent area

Based on examination of specimens and field observations of Elatostema J. R. Forster & G. Forster (Urticaceae) from China and its adjacent area, one new species, E. vietnamense Q. Lin & L. D. Duan from Bach Ma Natl. Park, Thua Thien‐Hue Province, Vietnam, is described and illustrated. Pellionia ambigua Wedd. from Khasi Hills, Churra, Assam (=Meghalaya), India and P. rhizomatosa Gagnep. from Annam, Vietnam are transferred as Elatostema ambiguum (Wedd.) Q. Lin and E. rhizomatosum (Gagnep.) Q. Lin, respectively. Elatostema glochidioides W. T. Wang from Guangxi and Guizhou and Provinces, China is regarded as a new synonym of E. ramosissimum Rein.     

贵州及湖南楼梯草属（荨麻科）植物新记录

本文报道荨麻科(Urticaceae)楼梯草属(ElatostemaJ.R.&G.Forst.)植物贵州新记录2种:疏晶楼梯草(E.hookerianum Wedd.)和显脉楼梯草(E.longistipulum Hand.-Mazz.),以及湖南新记录1种:西畴楼梯草(E.xi-chouense W.T.Wang)。     

Forage selection by Royle's pika (Ochotona roylei) in the western Himalaya,India

Forage selection decisions of herbivores are often complex and dynamic; they are modulated by multiple cues, such as quality, accessibility and abundance of forage plants. To advance the understanding of plant–herbivore interactions, we explored foraging behavior of the alpine lagomorph Royle's pika (Ochotona roylei) in Kedarnath Wildlife Sanctuary, India. Pika bite counts on food plants were recorded through focal sampling in three permanently marked plots. Food plant abundance was recorded by traditional quadrat procedures; forage selection was estimated with Jacob's selection index. Multiple food-choice experiments were conducted to determine whether forage selection criteria would change with variation in food plant composition. We also analyzed leaf morphology and nutrient content in both major food plants and abundantly available non-food plants. Linear regression models were used to test competing hypotheses in order to identify factors governing forage selection. Royle's pika fed primarily on 17 plant species and each forage selection decision was positively modulated by leaf area and negatively modulated by contents of avoided substances (neutral detergent fiber, acid detergent fiber, acid detergent lignin and tannin) in food plants. Furthermore, significance of the interaction term “leaf size × avoided substance” indicates that plants with large leaves were selected only when they had low avoided substance content. The forage selection criteria did not differ between field and laboratory experiments. The parameter estimates of best fit models indicate that the influence of leaf size or amount of avoided substance on pika forage selection was modulated by the magnitude of predation risk.     

中国荨麻科植物省级分布新记录

报道荨麻科6种1亚种1变种在我国6个省区分布的新记录,其中山东分布新记录的有海岛苎麻 (Boehmeria formosana),陕西分布新记录的有对叶楼梯草(Elatostema sinense),广东分布新记录的有台湾糯米团(Gonostegia parvifolia),贵州分布新记录的有显脉楼梯草(Elatostema longistipulum)和短毛楼梯草(E. nasutum var. puberulum),云南分布新记录的有高原荨麻(Urtica hyperborea),西藏分布新记录的有单蕊麻 (Droguetia iners subsp. urticoides)和细尾楼梯草(Elatostema tenuicaudatum)。     

Plant Trait Assembly Affects Superiority of Grazer's Foraging Strategies in Species-Rich Grasslands

Background

Current plant – herbivore interaction models and experiments with mammalian herbivores grazing plant monocultures show the superiority of a maximizing forage quality strategy (MFQ) over a maximizing intake strategy (MI). However, there is a lack of evidence whether grazers comply with the model predictions under field conditions.

Methodology/Findings

We assessed diet selection of sheep (Ovis aries) using plant functional traits in productive mesic vs. low-productivity dry species-rich grasslands dominated by resource-exploitative vs. resource-conservative species respectively. Each grassland type was studied in two replicates for two years. We investigated the first grazing cycle in a set of 288 plots with a diameter of 30 cm, i.e. the size of sheep feeding station. In mesic grasslands, high plot defoliation was associated with community weighted means of leaf traits referring to high forage quality, i.e. low leaf dry matter content (LDMC) and high specific leaf area (SLA), with a high proportion of legumes and the most with high community weighted mean of forage indicator value. In contrast in dry grasslands, high community weighted mean of canopy height, an estimate of forage quantity, was the best predictor of plot defoliation. Similar differences in selection on forage quality vs. quantity were detected within plots. Sheep selected plants with higher forage indicator values than the plot specific community weighted mean of forage indicator value in mesic grasslands whereas taller plants were selected in dry grasslands. However, at this scale sheep avoided legumes and plants with higher SLA, preferred plants with higher LDMC while grazing plants with higher forage indicator values in mesic grasslands.

Conclusions

Our findings indicate that MFQ appears superior over MI only in habitats with a predominance of resource-exploitative species. Furthermore, plant functional traits (LDMC, SLA, nitrogen fixer) seem to be helpful correlates of forage quality only at the community level.     

Fodder resources and feeding of semifree bison (<Emphasis Type="Italic">Bison bison</Emphasis>) on a steppe pasture in the Western Manych valley

In 2012–2013, the species composition, aboveground phytomass, and nutrition of freely ranging bison were investigated on a natural steppe pasture of the Western Manych valley. The aboveground mass of plants on the investigated pasture varied from 16.1 to 19.4 c/ha. The composition of the plants consumed by bison and their share in the bison’s diet were determined by microscopy of feces. In the snowless season, graminoids was the basis of the bison’s diet (79–87%). The use of forbs varied from 4.7 to 17.5%. Sedges were present in the forage in summer; they amounted to 6.5–15.4%. The quantitative assessment of the food selectivity was determined using the ratio of the share of a plant species in the diet to its portion in the plant community of the pasture. The most selected were Festuca valesiaca (the selectivity is 12.0), Agropyron sp. sp. (1.7), Polygonum patulum (1.2), and Carex sp. sp. (1.1). In other forage plants (Poa bulbojsa, Tanacetum achileifolium, and other forbs), the selectivity was 0.01–0.3. The nutritional value of fodder vegetation and food indexes (daily intake, digestibility of forage, consumption of metabolizable energy) were estimated. The digestibility was determined by the ratio of inert (undigestible) components (silicon, lignin) in the diet to their amount in the feces. The daily intake of forage was calculated based on the mass of released feces and digestibility of forage. In the snowless season, bison consumed from 6.3–7.0 to 9.2–9.9 kg/ind. (dry weight) per day. The maximum consumption (9.9 kg/ind.) was observed in summer. The digestibility of forage changed from 45 to 53% (the average is 50%). The consumption of metabolizable energy in different seasons varied from 0.60 to 0.91 MJ/kg^0.75/day, which corresponded to maintenance energy.     

Does the invasive Lupinus polyphyllus increase pollinator visitation to a native herb through effects on pollinator population sizes?

Invasive plants may compete with native species for abiotic factors as light, space and nutrients, and have also been shown to affect native pollination interactions. Studies have mainly focused on how invasive plants affect pollinator behaviour, i.e. attraction of pollinators to or away from native flowers. However, when an invasive plant provides resources utilized by native pollinators this could increase pollinator population sizes and thereby pollination success in natives. Effects mediated through changes in pollinator population sizes have been largely ignored in previous studies, and the dominance of negative interactions suggested by meta-analyses may therefore be biased. We investigated the impact of the invasive Lupinus polyphyllus on pollination in the native Lotus corniculatus using a study design comparing invaded and uninvaded sites before and after the flowering period of the invasive. We monitored wild bee abundance in transects, and visit rate and seed production of potted Lotus plants. Bumblebee abundance increased 3.9 times in invaded sites during the study period, whereas it was unaltered in uninvaded sites. Total visit rate per Lotus plant increased 2.1 times in invaded sites and decreased 4.4 times in uninvaded sites. No corresponding change in seed production of Lotus was found. The increase in visit rate to Lotus was driven by an increase in solitary bee visitation, whereas mainly bumblebees were observed to visit the invasive Lupinus. The mechanism by which the invasive increases pollinator visit rates to Lotus could be increased availability of other flower resources for solitary bees when bumblebees forage on Lupinus.     

Plant colonization in a gravel mine revegetated with Stylosanthes spp. in a Neotropical savanna

Tree establishment on degraded sites has failed in many tropical areas due to invasive plants and competition with herbs. The cultivation of plants that are capable of maintaining a site can avoid the dominance of invasive species. Some native species of the genus Stylosanthes (family Fabaceae) have been reported to effectively block invasive plants off ecosystems that are under restoration in Brazil. The aim of this study was therefore to evaluate the influence of perennial Stylosanthes spp. on plant colonization in a rehabilitated gravel mine in the Brazilian savanna region. Half of the mining area was sown with a mixture of three perennial Styloshantes species (treatment), while half of it remained unsown (control). The line intercept method was used to sample recruited plants within the mine after five years of site rehabilitation. Results showed that 31 plant species recruited in the gravel mine: 27 in the area sown with Stylosanthes spp. and 17 in the control area. Native species contributed for 47 % of the importance value index (IVI) in the treated area and 26 % in the control area. Two invasive exotic grasses made up 31 % of the plant community IVI in the treated area and 59 % in the control area. Perennial Stylosanthes spp. were supposed to block the development of incoming plants, but their presence actually allowed the area to be colonized by 1.6-fold more plant species than the control area. Ultimately, the area covered with Stylosanthes spp. evolved into a plant community that was more diverse and less dominated by exotic species than the control area.     

Crop Rotation Effects on Population Densities of Ectoparasitic Nematodes

The influence of rotation crop species on population densities of ectoparasitic nematode species common to soybean and corn fields of the North-Central region of the USA was studied for 5 years in 16 field blocks rotated to corn, soybeans, oats, wheat, and forage mixtures. Each block was sampled each year between mid-July and mid-August. High populations of Helicotylenchus pseudorobustus were maintained in all crops, especially corn. Tylenchorhynchus martini and Xiphinema americanum also developed with all crops, but a second year of corn depressed densities of both species. Paratylenchus projectus densities were high on soybeans and on forage consisting primarily of legumes.     

Current status in production and utilization of dihaploids from somatic hybrids between eggplant (Solanum melongena L.) and its wild relatives

The major constrains for practical exploitation of the somatic hybrids between eggplant and its wild relatives have been their sterility and tetraploidy which prevented their incorporation into breeding programs. Here we demonstrate that anther culture was successfully utilized to bring back the ploidy level to the diploid status in tetraploid interspecific hybrids between eggplant and the allied species S. integrifolium and S. aethiopicum gr. gilo. Both the relative species are resistant to Fusarium oxysporum f. sp. melongenae and to some strains of bacterial wilt (Ralstonia solanacearum) which are very destructive diseases of eggplant. Dihaploid androgenetic plants were obtained from the somatic hybrids, from the “double somatic hybrid” obtained by sexual cross of the two somatic hybrids [(eggplant + S. aethiopicum) × (eggplant + S. integrifolium)], and from tetraploid backcrossed plants between the somatic hybrid with S. aethiopicum and eggplant. Phenotypical, molecular, biological and biochemical characterization, and also artificial inoculation with Fusarium oxysporum are consistent with a recombination between the genomes of the species involved in the hybridizations. Dihaploids resistant to Fusarium were successfully backcrossed with eggplant. Besides their utility as potential valuable breeding materials, the introgressed lines obtained may be utilized in genetic and molecular studies about the resistance to Fusarium from S. integrifolium and S. aethiopicum gr. gilo.     

Determining spatio-temporal distribution of bee forage species of Al-Baha region based on ground inventorying supported with GIS applications and Remote Sensed Satellite Image analysis

In arid zones, the shortage of bee forage is critical and usually compels beekeepers to move their colonies in search of better forages. Identifying and mapping the spatiotemporal distribution of the bee forages over given area is important for better management of bee colonies. In this study honey bee plants in the target areas were inventoried following, ground inventory work supported with GIS applications. The study was conducted on 85 large plots of 50 × 50 m each. At each plot, data on species name, height, base diameter, crown height, crown diameter has been taken for each plant with their respective geographical positions. The data were stored, and processed using Trimble GPS supported with ArcGIS10 software program. The data were used to estimate the relative frequency, density, abundance and species diversity, species important value index and apicultural value of the species. In addition, Remotely Sensed Satellite Image of the area was obtained and processed using Hopfield Artificial Neural Network techniques. During the study, 182 species from 49 plant families were identified as bee forages of the target area. From the total number of species; shrubs, herbs and trees were accounting for 61%, 27.67%, and 11.53% respectively. Of which Ziziphus spina-christi, Acacia tortilis, Acacia origina, Acacia asak, Lavandula dentata, and Hypoestes forskaolii were the major nectar source plants of the area in their degree of importance. The average vegetation cover values of the study areas were low (<30%) with low Shannon’s species diversity indices (H′) of 0.5–1.52 for different sites. Based on the eco-climatological factors and the variations in their flowering period, these major bee forage species were found to form eight distinct spatiotemporal categories which allow beekeepers to migrate their colonies to exploit the resources at different seasons and place. The Remote Sensed Satellite Image analysis confirmed the spatial distribution of the bee forage resources as determined by the ground inventory work. An integrated approach, combining the ground inventory work with GIS and satellite image processing techniques could be an important tool for characterizing and mapping the available bee forage resources leading to their efficient and sustainable utilization.     

东北草原区的C3,C4牧草及其生态分布的初步研究

本文用RuBPCase活性/PEPCase活性的比值,鉴定东北草原区牧草资源中C_3、C_4植物。供测定45种中35种为首次鉴定。辅助观察禾草类Kranz结构。在此基础上,对其中11种C_3、C_4优势牧草的地理分布、物候谱及其相对优势度与土壤pH值和含盐量之间的关系进行了研究。结果表明,C_3植物30种,隶属于10科24属,C_4植物15种,隶属于5科9属。与C_3植物相比,在高温、强光照和降水量大的季节,C_4植物显示其更高的相对生长优势,在纬度较低和盐碱化区域,C_4植物具有相对分布优势。C.4草相对优势度与土壤pH值和含盐量的相关系数分别为0.826和0.760,而C_3植物均为负值。     

A new species of the Melanesian genus Kanaliella (Coleoptera: Cleridae)

Kanaliella balkorum n. sp., a new species of checkered beetles (Cleridae) from New Caledonia is described and figured.urn:lsid:zoobank.org:pub:FA16DD22-2C83-4677-8B1C-E3A317BF150E.     

The pollination efficiency of a pollinator depends on its foraging strategy,flowering phenology,and the flower characteristics of a plant species

Honey bees and stingless bees are generalist visitors of several wild and cultivated plants. They forage with a high degree of floral fidelity and thereby help in the pollination services of those plants. We hypothesized that pollination efficiency might be influenced by flowering phenology, floral characteristics, and resource collection modes of the worker bees. In this paper, we surveyed the foraging strategies of honey bees (Apis cerana, Apis dorsata, and Apis florea) and stingless bees (Tetragonula iridipennis) concerning their pollination efficiencies. Bees showed different resource gathering strategies, including legitimate (helping in pollination as mixed foragers and specialized foragers) and illegitimate (serving as nectar robbers and pollen thieves) types of flower visitation patterns. Foraging strategies are influenced by the shape of flowers, the timing of the visitation, floral richness, and bee species. Honey bees and stingless bees mainly acted as legitimate visitors in most plants studied. Sometimes honey bees served as nectar robbers in tubular flowers and stingless bees as pollen thieves in large-sized flowers. Among the legitimate categories, mixed foragers have a comparatively lower flower visitation rate than the specialized nectar and pollen foragers. However, mixed foragers have greater abundance and higher values of the single-visit pollination efficiency index (PEi) than nectar and pollen foragers. The value of the combined parameter ‘importance in pollination (PI)’ was thus higher in mixed foragers than in nectar and pollen foragers.     

Diversity,Abundance and Community Structure of Benthic Macro- and Megafauna on the Beaufort Shelf and Slope

Diversity and community patterns of macro- and megafauna were compared on the Canadian Beaufort shelf and slope. Faunal sampling collected 247 taxa from 48 stations with box core and trawl gear over the summers of 2009–2011 between 50 and 1,000 m in depth. Of the 80 macrofaunal and 167 megafaunal taxa, 23% were uniques, present at only one station. Rare taxa were found to increase proportional to total taxa richness and differ between the shelf ( 100 m) where they tended to be sparse and the slope where they were relatively abundant. The macrofauna principally comprised polychaetes with nephtyid polychaetes dominant on the shelf and maldanid polychaetes (up to 92% in relative abundance/station) dominant on the slope. The megafauna principally comprised echinoderms with Ophiocten sp. (up to 90% in relative abundance/station) dominant on the shelf and Ophiopleura sp. dominant on the slope. Macro- and megafauna had divergent patterns of abundance, taxa richness ( diversity) and diversity. A greater degree of macrofaunal than megafaunal variation in abundance, richness and diversity was explained by confounding factors: location (east-west), sampling year and the timing of sampling with respect to sea-ice conditions. Change in megafaunal abundance, richness and diversity was greatest across the depth gradient, with total abundance and richness elevated on the shelf compared to the slope. We conclude that megafaunal slope taxa were differentiated from shelf taxa, as faunal replacement not nestedness appears to be the main driver of megafaunal diversity across the depth gradient.     

海蜇养殖对池塘底泥营养盐和大型底栖动物群落结构的影响

2009年5-9月,对荣成靖海湾大型养殖池塘海蜇(Rhopilema esculentum Kishinouye)养殖期间与养殖期前后底泥营养盐及大型底栖动物群落结构变化进行了研究。结果表明,7月份海蜇养殖期间,由于海蜇的避光性而产生的上下浮动的行为特征造成了对水体的扰动作用, 与海蜇的生物沉积作用共同导致养殖海区(实验点)与邻近非养殖海区(对照点)之间各项底泥营养盐指标均存在显著性差异,其中,实验点氨氮(NH₄-N)、硝氮(NO₃-N)和沉降速率(sedimentation rate, SR)显著高于对照点,实验点叶绿素a(Chla)、总有机物(TOM)和总有机碳(TOC)含量显著低于对照点。多变量聚类分析结果表明,海蜇养殖对养殖池塘的大型底栖动物群落结构产生显著影响,并且7月份实验点大型底栖动物生物多样性指数(H')和均匀度指数(J) 随海蜇放养显著增大,并显著高于对照点。大型底栖动物群落多样性指数与沉降速率(SR)和底泥TOM含量分别表现出显著正相关和负相关,而与其他营养盐指标无显著相关性。     

Water quality changes in relation to Diptera community patterns and diversity measured at an organic effluent impacted stream in the Niger Delta,Nigeria

Impact of abattoir effluents (characterized by intestinal and stomach contents of slaughtered animals, ashes from roasted animals and blood stains) on water quality, distribution and abundance of Diptera were investigated in an urban stream, River Orogodo, Southern Nigeria, from July 2003 to June 2004. Water quality changes indicated significant differences (p < 0.05) in conductivity, dissolved oxygen, BOD₅, COD, total hardness, nitrate-nitrogen and phosphate-phosphorus between the three stations sampled. Higher values of these parameters were observed at the impacted station. The abundance and community structure of Diptera patterns, especially Chironomidae, Culicidae and Syrphidae families (all indicative of poor water quality) showed strong evidence of impact from the abattoir effluents. Comparisons of abundance values demonstrated high significance (p < 0.05) between the impacted station and the upstream (station 1) and downstream station (station 3). Shannon index and Berger–Parker dominance were greater at the impacted station (station 2). Analysis of faunal similarities showed that upstream station 1(unpolluted site) was significantly different from stations 2 and 3. The distinct taxa found in station 2 (the impacted station) suggest that the organic input from the abattoir favoured their abundance as most of them were opportunistic species.     

Hierarchical resource selection by impala in a savanna environment

The factors that affect resource selection by a foraging herbivore can vary according to the resources or conditions associated with particular levels of organization in the environment, and to the scales over which the herbivore perceives and responds to those resources and conditions. To investigate the role of forage in this hierarchical process, we studied resource selection by a mixed‐feeding large herbivore, the impala (Aepyceros melampus). We focussed on three spatial scales: plant species, feeding station and feeding patch. In paired sites where impala were and were not observed, we identified the plant species from which animals fed, the attributes of the plants, and the characteristics of the broader site. Across all three scales, plant species available as forage was central in determining resource selection by impala. At the species level, that effect was modified by the nutritional quality (greenness) and whether it was during a period of forage abundance or scarcity (season). At the feeding‐station level, overall greenness and biomass of the station were important, but their effects were modified by the season. At the feeding‐patch level, broader‐scale factors such as the type of vegetation cover had an important influence on resource selection. The grass Panicum maximum was a preferred forage species and a key resource determining the locations of feeding impala. Our findings support the idea that selection by a foraging herbivore at fine scales (i.e. diet selection) can have consequences for broader‐scale selection that result in observed patterns of habitat use and animal distribution.