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11.
A new genus and species of Scoliidae (Hymenoptera), Sinoproscolia yangshuwanziensis gen. et sp. nov., is described from the Lower Cretaceous Yixian Formation in Inner Mongolia, China and attributed to the subfamily Proscoliinae. Some characteristics, including complete crossveins 1r-rs and 2r-m in the forewing, and a free section present in almost all longitudinal veins indicate a basal position of the new genus in Proscoliinae. The presence of vein 2A suggests its atavistic origin in Sinoproscolia gen. nov. rather than a true plesiomorphy. 相似文献
12.
Revision of the Cenomanian echinoids deposited in the Cairo Geological Museum resulted in the erection of two new genera with two new species of regular echinoids. The first, Notatudiadema rekeibensis gen. and sp. nov. is established for specimens from the Cenomanian of Gabal El-Rekeib, southeast the Maghara massif, north Sinai to accommodate diadematoid echinoids having hemi-crenulate ambital and sub-ambital interambulacral tubercles with the adapical part of platform non-crenulate and the adoral one of same tubercle coarsely crenulate. The second is Aegyptiaris halalensis gen. and sp. nov., erected for material from the lower Cenomanian of Gabal El-Halal, northeast Sinai as an emiratiid echinoid with throughout polyporus ambulacra and extremely reduced adapical ambulacral tubercles. The functional morphology and paleobiology of these taxa are also discussed. A new family is established: family Monodiadematidae fam. nov. 相似文献
13.
西鄂尔多斯维管植物区系特征分析 总被引:3,自引:1,他引:2
通过在西鄂尔多斯地区几年的植物标本采集以及参考前人对该地区植物名录的记载,对西鄂尔多斯地区野生维管植物种类组成、生活型、水分生态类型及植物区系地理成分进行了分析研究。结果表明:①西鄂尔多斯地区的野生维管植物共有64科、215属、433种;②植物的生活型以多年生草本为主,占52.66%,其他为乔木占0.69%、灌木占14.09%、半灌木占6.93%、一或二年生草本占24.25%、草质藤本占0.92%,类短命植物占0.46%;③植物的水分生态类型以旱生(包括强旱生、旱生和中旱生)为主,占49.42%,中生植物(包括旱中生、中生、湿中生)占47.58%,湿生植物占1.85%,水生植物仅占1.15%;④西鄂尔多斯地区植物区系地理成分组成复杂多样,在温带区系性质为主体的背景下,受欧亚草原区系、东亚森林区系、亚洲中部荒漠区系及古地中海区系的影响。 相似文献
14.
I. A. E. Bayly 《新西兰海洋与淡水研究杂志》2013,47(2):105-117
The fauna and chemical composition of two athalassic saline waters located near central Otago are discussed, and available rainfall and evaporation data for the region summarised. One water (dominated by Na and C1) had a salinity of 15‰ and contained the rotifer Brachionus plicatilis, the copepod Microcyclops monacanthus, the ostracod Diacypris, and larvae of the dipteran Ephydrella The second water (dominated by Na and HCO3) had a salinity of 6‰ and contained larvae of Ephydrella (adults of E. novaezealandiae occurred on the shore), and the hemipterans Sigara arguta, Anisops wakefieldi and Anisops assimilis The relationship between Microcyclops monacanthus and M. arnaudi (an Australian species), and the basis of their current taxonomic separation is discussed in some detail. At a minimum, the faunas of Australian and New Zealand athalassic saline waters have in common the following distinctive (non‐cosmopolitan) forms: Ephydrella, Diacypris, and two closely related halobiont species of Microcyclops 相似文献
15.
R. C. Murdoch 《新西兰海洋与淡水研究杂志》2013,47(2):175-178
Plaxiphora boydeni n.sp. from wave‐exposed rocky shores of southern New Zealand is described and illustrated. This is the first published record of the genus from the New Zealand mainland. P. boydeni is readily distinguished from the 2 other New Zealand species of the genus, which occur in the subantarctic region, by the absence of bristle‐tufts on the girdle. 相似文献
16.
Type-specific and indicator taxa of phytoplankton as a quality criterion for assessing the ecological status of Finnish boreal lakes 总被引:6,自引:0,他引:6
Key issues in the implementation of the Water Framework Directive are classification of lakes using biological quality parameters and type-specific reference conditions. This work is one of three studies considering different metrics of phytoplankton in the classification of ecological status. Phytoplankton was studied in a total of 55 Finnish boreal lakes, including 32 reference lakes. We tested the suitability of taxonomic composition and abundance of phytoplankton groups for biological classification. We also preliminarily determined the type-specific taxa for the studied lakes. The type-specific taxa for reference conditions are coincidently the indicator species/taxa for high ecological status. Interestingly, some taxa type-specific for impacted oligo-humic lakes proved to be the type-specific taxa for humic reference lakes. The pressure of human impact was observed not only as increase of biomass but also as changes in the species composition. The phytoplankton composition indicated the ecological status of impacted lakes moderately well. There was some variation in the indications given by different algal groups, probably due to the preliminary class boundaries used. However, the preliminary combination of indicative parameters to estimate the ecological status of the studied impacted lakes was in general in accordance with earlier classification of water quality in Finnish lakes. 相似文献
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19.
Precipitation is the most fundamental input of water for terrestrial ecosystems. Most precipitation inputs are vertical, via rain, but can be horizontal, via wind‐driven rain and snow, or, in some ecosystems such as tropical montane cloud forests (TMCFs), via fog interception. Fog interception can be particularly important in ecosystems where fog is frequently present and there are seasonal periods of lower rainfall. Epiphytes in trees are a major ecological component of TMCFs and are particularly dependent on fog interception during periods of lower rainfall because they lack access to soil water. But assessing fog interception by epiphytes remains problematic because: (i) a variety of field or laboratory methods have been used, yet comparisons of interception by epiphytes versus interception by various types of fog gauge are lacking; (ii) previous studies have not accounted for potential interactions between meteorological factors. We compared fog interception by epiphytes with two kinds of commonly used fog gauges and developed relations between fog interception and meteorological variables by conducting laboratory experiments that manipulated key fog characteristics and from field measurements of fog interception by epiphytes. Fog interception measured on epiphytes was correlated with that measured from fog gauges but was more than an order of magnitude smaller than the actual measurements from fog gauges, highlighting a key measurement issue. Our laboratory measurements spanned a broad range of liquid water content (LWC) values for fog and indicate how fog interception is sensitive to an interaction between wind speed and LWC. Based on our results, considered in concert with those from other studies, we hypothesize that fog interception is constrained when LWC is low or high, and that fog interception increases with wind speed for intermediate values of LWC—a net result of deposition, impaction, and evaporation processes—until interception begins to decrease with further increases in wind speed. Copyright © 2007 John Wiley & Sons, Ltd. 相似文献
20.
本文对本实验室制备的小口径人工血管的机械性质进行了表征并与大鼠腹主动脉和犬股动脉进行了比较。人工血管的内径分别为1.5、2、3和4mm,大鼠腹主动脉和犬股动脉内径分别为1.5和3mm。人工血管的加压扩张内径与自然内径有显著性差异(P0.05);其吸水率均高于270%,内径越大,吸水率越高;其内表面材料致密,外表面材料的孔隙率是(96.24±3.99)%;其水渗透压均高于8.78kPa,水渗透量均在低于2~3mL·min-1·cm-2;其爆破压在532KPa左右,均高于犬股动脉(P0.05);其纵向拉伸率均高于大鼠腹主动脉(P0.05),但低于犬股动脉(P0.05),断裂拉伸率均低于大鼠腹主动脉和犬股动脉(P0.05),其耐缝合强度均高于大鼠腹主动脉(P0.05),顺应性均低于犬股动脉(P0.05)。基于上述信息,这种小口径人工血管能满足大鼠腹主动脉和犬股动脉血管置换的要求,但仍需改进。 相似文献