秦岭落叶阔叶林25 ha森林动态监测样地物种组成与群落特征

秦岭落叶阔叶林是温带-亚热带过渡区保存较好的植被类型, 群落结构复杂。为了研究该过渡区植被的生物多样性维持机制, 按照CTFS (Center for tropical Forest Science)和中国森林生物多样性监测网络(CForBio)的建设标准, 于2015年在陕西省佛坪国家级自然保护区的落叶阔叶林建立了一块面积25 ha的动态监测样地。本文对样地内胸径(DBH) ≥ 1 cm的所有木本植物进行了调查和统计, 分析了其物种组成、区系特征、径级结构和空间分布格局。结果表明: 样地内DBH ≥ 1 cm的木本植物独立个体有47,739株, 隶属于36科66属119种。温带区系成分的科和属分别占总科数和总属数的41.18%和60.00%, 温带区系特征明显。稀有种有51种, 占总树种的42.86%。落叶树种有106种, 占总树种的89.07%, 在样地内占绝对优势。重要值≥ 1的物种共有20个, 分别占样地总个体数和总胸高断面积的70.35%和57.41%, 重要值最大的物种分别是乔木层的锐齿栎(Quercus aliena var. acutesrrata)、亚乔木层的水榆花楸(Sorbus alnifolia)和灌木层的刺叶栎(Q. spinosa)。样地内所有个体的平均胸径为8.61 cm, 整体径级分布呈倒”J”型, 小径级个体较多, 群落更新良好。除了太白杨(Populus purdomii), 样地内优势种表现出大尺度的聚集分布, 且它们的分布与生境紧密相关, 不同物种表现出不同的生境偏好。     

江西省维管植物分布新纪录

报道江西省维管植物分布2 个新纪录属——蔓虎刺属Mitchella Linn.及裂禾蕨属Tomophyllum (E.Fournier) Parris,及3 个新纪录种——蔓虎刺Mitchella undulata Sieb. et Zucc.、裂禾蕨Tomophyllum donianum(Sprengel) Fraser-Jenkins & Parris、土佐景天Sedum tosaense Makino,均发现于罗霄山脉地区。     

Foraminifers and algae of the late Tournaisian–early Viséan boundary interval (MFZ8–9) in the Gachal Formation (Central Iran)

Three sections of the Gachal Formation, Tang-e Vaveila, Rahdar, and Bakhshi, located in the Kalmard area near the Tabas town (Central Iran) are revised. Tang-e Vaveila is dated as latest Tournaisian (upper MFZ8) to early Viséan (upper MFZ9); Rahdar is latest Tournaisian (latest MFZ8); and Bakhshi exposes the whole early Viséan (lower and upper MFZ9) succession. The upper MFZ8 subzone is indicated by the presence of Eoparastaffellina ex gr. rotunda; the lower MFZ9 subzone by the appearance of Eoparastaffella ex gr. simplex, and the upper MFZ9 subzone by the more or less concomitant appearances of Eostaffella and Lapparentidiscus. Among the foraminiferal assemblages, the endothyroids and loeblichioids are diversified, whereas the eoparastaffellins, tournayelloids and lituotubelloids remain rare. Regionally, the tetrataxins are interesting, because five species of Tetrataxis succeed one another across the MFZ9 biozone. Rich populations of Eotextularia were also observed. Incertae sedis algae are relatively diversified with the classical moravamminales and aoujgaliales. An interesting true alga is mentioned, but left in open nomenclature, as Epimastoporeae indet. Among the other microfossils, Cryptophyllus, Hamulusella?, Draffania, and hexaphyllids are noteworthy. The new taxa are: Eoparastaffellinae n. subfam., Endolaxina paralaxa n. sp., and Vissarionovella? iranica n. sp.     

Cryptosporidium spp., Giardia intestinalis,and Enterocytozoon bieneusi in Captive Non-Human Primates in Qinling Mountains

Non-human primates (NHPs) are confirmed as reservoirs of Cryptosporidium spp., Giardia intestinalis, and Enterocytozoon bieneusi. In this study, 197 fresh fecal samples from 8 NHP species in Qinling Mountains, northwestern China, were collected and examined using multilocus sequence typing (MLST) method. The results showed that 35 (17.8%) samples were positive for tested parasites, including Cryptosporidium spp. (3.0%), G. intestinalis (2.0%), and E. bieneusi (12.7%). Cryptosporidium spp. were detected in 6 fecal samples of Macaca mulatta, and were identified as C. parvum (n=1) and C. andersoni (n=5). Subtyping analysis showed Cryptosporidium spp. belonged to the C. andersoni MLST subtype (A4, A4, A4, and A1) and C. parvum 60 kDa glycoprotein (gp60) subtype IId A15G2R1. G. intestinalis assemblage E was detected in 3 M. mulatta and 1 Saimiri sciureus. Intra-variations were observed at the triose phosphate isomerase (tpi), beta giardin (bg), and glutamate dehydrogenase (gdh) loci, with 3, 1, and 2 new subtypes found in respective locus. E. bieneusi was found in Cercopithecus neglectus (25.0%), Papio hamadrayas (16.7%), M. mulatta (16.3%), S. sciureus (10%), and Rhinopithecus roxellana (9.5%), with 5 ribosomal internal transcribed spacer (ITS) genotypes: 2 known genotypes (D and BEB6) and 3 novel genotypes (MH, XH, and BSH). These findings indicated the presence of zoonotic potential of Cryptosporidium spp. and E. bieneusi in NHPs in Qinling Mountains. This is the first report of C. andersoni in NHPs. The present study provided basic information for control of cryptosporidiosis, giardiasis, and microsporidiosis in human and animals in this area.     

Biophysical analysis of afromontane forest community types at Mount Kasigau,Kenya

This study examines how biophysical site conditions differ in relation to the distribution of forest community types at Mount Kasigau, Kenya, in the Eastern Arc. Topographic measures of elevation, slope, curvature and aspect were derived from a 30‐m DEM and temperature and moisture conditions collected from 19 field data loggers for June 2011–2012 measured seasonal change along the steep elevational gradient (1000 m) from bushland to evergreen forest. Nonparametric statistical analyses then compared topographic and climatic conditions among eight ecologically classified forest types. Steep lapse rates in temperature and available moisture support abrupt changes in canopy physiognomy, but dew points declined with elevation. The Kruskal–Wallis test showed significant differences in the elevation, slope, temperature, dew point and relative humidity conditions among the eight forest types. These biophysical conditions are more discrete for Acacia‐Commiphora bushland and cloud forest but not significantly different between riverine forest, lower montane woodlands I and II and Euphorbia quinquecostata woodland, and between semi‐evergreen woodland and evergreen forest. Biophysical conditions and their influence on the distribution of forest types across a heterogeneous mountain landscape are important to understand and monitor in this unpredictably changing tropical seasonal climate.     

Of plants and pikas: evidence for a climate-mediated decline in forage and cache quality

Background: Animals that hoard food to mediate seasonal deficits in resource availability might be particularly vulnerable to climate-mediated reductions in the quality and accessibility of food during the caching season. Central-place foragers might be additionally impacted by climatic constraints on their already restricted foraging range.

Aims: We sought evidence for these patterns in a study of the American pika (Ochotona princeps), a territorial, central-place forager sensitive to climate.

Methods: Pika food caches and available forage were re-sampled using historical methods at two long-term study sites, to quantify changes over two decades. Taxa that changed in availability or use were analysed for primary and secondary metabolites.

Results: Both sites trended towards warmer summers, and snowmelt trended earlier at the lower latitude site. Graminoid cover increased at each site, and caching trends appeared to reflect available forage rather than primary metabolites. Pikas at the lower latitude site preferred species higher in secondary metabolites, known to provide higher-nutrient winter forage. However, caching of lower-nutrient graminoids increased in proportion with graminoid availability at that site.

Conclusions: If our results represent trends in climate, cache quality and available forage, we predict that pikas at the lower latitude site will soon face nutritional deficiencies.     

新疆微孢衣属地衣新记录种

报道了采自新疆布尔津县五彩滩的微孢衣属(Acarospora A.Massal.)地衣两个新记录种,即:中国新记录种美国微孢衣(Acarospora americana H.Magn.)和新疆新记录种翡翠微孢衣(Acarospora smaragdula(Wahlenb.)A.Massal.),详细描述了这两种地衣的形态特征、解剖特征及生境。     

武陵山东部蚤类区系及不同样地群落物种多样性比较

于2000～2004年对武陵山东部7个不同样地、3个不同海拔梯度和6个不同生境类型的蚤类,进行了5年调查与研究.结果:1)在获得的7科17属30种4 320只蚤类中,有4种为古北界种类,占13.33%,22种为东洋界种类,占73.34%,4种为广布种,占13.33%;该结果与云南无量山及临沧地区的蚤类有着相同或相似的区系渊源,而与一江之隔的大巴山东部地区区系则明显不同,该地区以古北界成分为优势;2)武陵山东部地区蚤类的垂直分布规律主要表现在,1 100 m以下主要为东洋界成分,1 200 m以上有少量古北界种类分布,并随海拔升高,古北界成分略有增加;3)在7个不同样地中,物种丰富度和个体数量随海拔升高而增加,在优势种上,多数样地以偏远古蚤为优势,但在优势数量上缺乏明显规律性,并不是随海拔升高而增加;4)在6个不同生境类型中,优势种与优势数量都具明显的规律性,其中以偏远古蚤为主分为两组,山脊侧缘林、小溪山边林和坡地林为一组,人工林和农田山侧灌木林为另一组,前者平均优势数量达80.03%,后者优势数量在31.56%～48.92%之间;5)相似性系数(q值):在整个山体多数样地中,由北向南相似性系数(q值)随海拔降低和空间距离增大而逐渐降低,仅绿丛坡与牛庄、绿丛坡与独岭有例外,表明整个山体植被的片断化、或斑块化,一方面加剧或减低了样地与样地之间蚤类群落的相似程度,另一方面还要受海拔及空间距离的双重影响与制约,即海拔高度和空间距离愈大,蚤类群落的相似性及多样性越低,山体的片断、斑块或破碎化就越明显,这显然与人为过多或过频干扰有关.     

大兴安岭呼中区紫貂生境格局变化及采伐的影响

本文根据紫貂（Martes zibellina）行为生态学特征,利用景观生态学的原理和技术,将大兴安岭呼中区紫貂生境划分成最适、一般适宜和非适宜三种类型。以其紧邻的呼中自然保护区核心区1989年的生境格局代表呼中区1970年开发前的原始生境,揭示原始生境、1989年、2000年3个时期紫貂生境格局及变化。结果表明,1970-2000年紫貂生境格局持续恶化,已极不利于紫貂的生存。适宜生境向非适宜生境呈单一方向转变,且适宜生境由沟谷两侧向远离河谷的森林腹地大幅度萎缩。生境格局变化与经营时问长短关系密切,原始状态是以适宜生境为基质的均质状态,开发至一定时期,生境格局的异质化程度增大,继续开发则异质化程度又减小,形成以非适宜生境为基质的相对均质状态。大于巢区最小面积f4km0）的生境斑块的面积百分比、斑块密度明显下降,斑块间距离显著增大。进而对导致生境格局变化的要素进行分析后发现,持续采伐是紫貂生境格局变化的主要驱动因子,采伐改变了植被条件,而植被条件的非适宜性造成了紫貂非适宜生境。1989-2000年的采伐格局也并不合理,各年伐区在研究区内均匀分布,采伐设计时没有考虑动物生境保护。但可以推断,1999年后开始逐步实施的“天然林保护工程”有利于紫貂生境的恢复,本研究强调森林采伐经营的空间格局与动物生境保护之间的关系,旨在促进决策部门将生物保护作为采伐经营政策制定的重要决策因子。     

Le(x) glycan mediates homotypic adhesion of embryonal cells independently from E-cadherin: a preliminary note

Le(x) glycan and E-cadherin (Ecad) are co-expressed at embryonal stem (ES) cells and embryonal carcinoma (EC) cells. While the structure and function of Ecad mediating homotypic adhesion of these cells have been well established, evidence that Le(x) glycan also mediates such adhesion is weak, despite the fact that Le(x) oligosaccharide inhibits the compaction process. To provide stronger evidence, we knocked out Ecad gene in EC and ES cells to establish F9 Ecad (-/-) and D3M Ecad (-/-) cells, which highly express Le(x) glycan but do not express Ecad at all. Both F9 Ecad (-/-) and D3M Ecad (-/-) cells displayed strong autoaggregation in the presence of Ca(2+), while PYS-2 cells, which express trace amount of Ecad and undetectable level of Le(x) glycan, did not display autoaggregation. In addition, F9 Ecad (-/-) and D3M Ecad (-/-) cells displayed strong adhesion to plates coated with Le(x) glycosphingolipid (III(3)FucnLc4Cer), in dose-dependent manner, in the presence of Ca(2+). Thus, ES or EC cells display autoaggregation and strong adhesion to Le(x)-coated plates in the absence of Ecad, further supporting the notion of Le(x) self-recognition (i.e., Le(x)-to-Le(x) interaction) in cell adhesion.