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931.
932.
933.
CLEMENS KÜPPER GAVIN J. HORSBURGH DEBORAH A. DAWSON RICHARD FFRENCH‐CONSTANT TAMS SZKELY TERRY BURKE 《Molecular ecology resources》2007,7(1):35-39
We isolated 45 new Kentish plover (Charadrius alexandrinus) microsatellite loci. These were tested for polymorphism in 42 Kentish plovers breeding in the Çukurova Delta, Turkey. Thirty‐six of the 45 loci were polymorphic with observed heterozygosity varying between 0.22 and 0.93. Genotypes of individuals of known sex indicated that two loci were sex‐linked (Calex‐26 is located on the Z chromosome and Calex‐31 on the W chromosome). Additionally, we tested all loci for amplification in four other species of Charadridae (Kittlitz's plover, Madagascar plover, three‐banded plover and white‐fronted plover). On average 34 loci amplified per species (range 29–36). 相似文献
934.
We analyzed long-term winter survey data (1956–2007) for three endangered waterbirds endemic to the Hawaiian Islands, the
Hawaiian moorhen (Gallinula chloropus sandvicensis), Hawaiian coot (Fulica alai), and Hawaiian stilt (Himantopus mexicanus knudseni). Time series were analyzed by species–island combinations using generalized additive models, with alternative models compared
using Akaike information criterion (AIC). The best model included three smoothers, one for each species. Our analyses show
that all three of the endangered Hawaiian waterbirds have increased in population size over the past three decades. The Hawaiian
moorhen increase has been slower in more recent years than earlier in the survey period, but Hawaiian coot and stilt numbers
still exhibit steep increases. The patterns of population size increase also varied by island, although this effect was less
influential than that between species. In contrast to earlier studies, we found no evidence that rainfall affects counts of
the target species. Significant population increases were found on islands where most wetland protection has occurred (Oahu,
Kauai), while weak or no increases were found on islands with few wetlands or less protection (Hawaii, Maui). Increased protection
and management, especially on Maui where potential is greatest, would likely result in continued population gains, increasing
the potential for meeting population recovery goals. 相似文献
935.
报道中国云南巨须隐翅虫属Oxyporus Fablicius和巨须隐翅虫亚属subgenus Oxyporus的4个种,其中包括2新种,玉龙巨须隐翅虫Oxyporus (Oxyporus) yulong sp.nov.和李氏巨须隐翅虫O.(O.)lii sp.nov.,补充了仙台巨须隐翅虫O.germanus Sharp和横沟巨须隐翅虫O.transversesulcatus Bernhauer新的地理分布。 相似文献
936.
HARALD PAULI MICHAEL GOTTFRIED KARL REITER CHRISTIAN KLETTNER GEORG GRABHERR 《Global Change Biology》2007,13(1):147-156
High mountain ecosystems are defined by low temperatures and are therefore considered to react sensitively to climate warming. Responding to observed changes in plant species richness on high peaks of the European Alps, an extensive setup of 1 m × 1 m permanent plots was established at the alpine‐nival ecotone (between 2900 and 3450 m) on Mount Schrankogel, a GLORIA master site in the central Tyrolean Alps, Austria, in 1994. Recording was repeated in a representative selection of 362 quadrats in 2004. Ten years after the first recording, we observed an average change in vascular plant species richness from 11.4 to 12.7 species per plot, an increase of 11.8% (or of at least 10.6% at a 95% confidence level). The increase in species richness involved 23 species (about 43% of all taxa found at the ecotone), comprising both alpine and nival species and was pronouncedly higher in plots with subnival/nival vegetation than in plots with alpine grassland vegetation. Only three species showed a decrease in plot occupancy: one was an annual species, one was rare, and one a common nival plant that decreased in one part of the area but increased in the uppermost part. Species cover changed in relation to altitudinal preferences of species, showing significant declines of all subnival to nival plants, whereas alpine pioneer species increased in cover. Recent climate warming in the Alps, which has been twice as high as the global average, is considered to be the primary driver of the observed differential changes in species cover. Our results indicate an ongoing range contraction of subnival to nival species at their rear (i.e. lower) edge and a concurrent expansion of alpine pioneer species at their leading edge. Although this was expected from predictive distribution models and different temperature‐related habitat preferences of alpine and nival species, we provide first evidence on – most likely – warming‐induced species declines in the high European Alps. The projected acceleration of climate warming raises concerns that this phenomenon could become the major threat to biodiversity in high mountains. 相似文献
937.
为了探讨氟康唑作用机制,观察它对热带念珠菌作用后存活率、活性氧(Reactive oxygen species,ROS)、线粒体膜电位(Mitochondrial membrane potential,△Ψm)和细胞周期的变化。参照NCCLS M27-A方案的微量稀释法测定氟康唑对热带念珠菌的最低抑菌浓度(MIC);热带念珠菌与不同浓度氟康唑共同培养后用流式细胞术(Flow cytometry,FCM)分析热带念珠菌存活率、ROS、线粒体膜电位△Ψm和细胞周期的变化。结果表明,氟康唑作用后,热带念珠菌氟康唑耐药株的存活率、ROS、线粒体膜电位△Ψm和细胞周期各期比例均没有明显变化;而热带念珠菌氟康唑敏感株的存活率和线粒体膜电位△Ψm明显下降,ROS明显升高,而且大部分热带念珠菌阻滞于G2/M期,并出现明显凋亡峰,呈一定的时间剂量依赖关系。自由基清除剂谷胱甘肽抑制热带念珠菌ROS的产生,阻止细胞周期G2/M期阻滞和降低凋亡。由此可见,氟康唑可能通过刺激热带念珠菌产生过多ROS,并使线粒体膜电位△Ψm下降,从而诱导热带念珠菌凋亡。 相似文献
938.
施氮对几种草地植物生物量及其分配的影响 总被引:4,自引:0,他引:4
为了研究施氮对不同草地植物生物量及其分配的影响,以及温带草地生态系统碳交换过程对氮素的响应,在内蒙古太仆寺旗农田-草地生态系统野外站,以4种草地植物:紫花苜蓿(Medicago sativa L.)、高丹草(Sorghum bicolor L.) 、羊草(Leymus chinensis T.)和小叶锦鸡儿(Caragana microphylia L.)为材料,进行了3种氮素水平 的盆栽控制实验。研究结果表明:施氮显著促进了4种植物地上生物量的积累,紫花苜蓿在中氮水平地上生物量最大,较对照增加了24.8%,高丹草、羊草、小叶锦鸡儿在高氮水平地上生物量最大,分别较对照增加了45.6%、39.3%和72.2%。4种植物在中氮水平地下生物量最大,而细根(直径≤2mm)生物量随施氮量的增加显著减少。羊草根茎生物量及其分配比例随施氮量的增加而增大。施氮显著降低了4种植物的根冠比,紫花苜蓿的根冠比在中氮水平时最小,为1.62,高丹草、羊草、小叶锦鸡儿的根冠比在高氮水平时最小,分别为0.57、1.02和0.41。随施氮量的增加,植物地下部分特别是细根的分配比例显著降低,地上部分分配比例显著增加。不同植物对施氮水平的响应不同,相比豆科植物,施氮显著促进禾本科植物生物量积累,并使其生物量分配格局发生显著改变。 相似文献
939.
940.
记述采自辽宁、河南、山东、浙江等省的小腹茧蜂属Microgaster Latreille2新种和1中国新记录种;刻胸小腹茧蜂Microgaster punctithorax,sp.nov.、玉主螟小茧蜂Microgaster ostriniae,sp.nov.和平原小腹茧蜂Microgaster campestris Tobias1964,new record。模式标本保存在浙江大河保护系昆虫标本 相似文献