Comparison of stream benthic invertebrate assemblages among forest types in the temperate region of Japan

We compared benthic invertebrate assemblages among headwater streams in several forest types in Japan. Forests were divided into three clusters based on vegetation composition: old-growth broad-leaved forest, planted coniferous forest, and mixed forest. The numbers of individuals and families and the diversity (Shannon-Wiener) of benthic invertebrate assemblages did not differ significantly among the three forest clusters. However, principal components analysis of family abundance showed differences in the benthic invertebrate assemblages among the three forest clusters. No environmental factors were correlated with these differences. Benthic invertebrate assemblages differed depending on forest composition. The abundances of Taeniopterygidae and Athericidae in old-growth broad-leaved forest were significantly greater than in planted coniferous forest. The abundances of Heptageniidae, Baetiidae, Stenopsychidae, Uenoidae, Chironomidae, and Potamidae in planted coniferous forest were significantly greater than in old-growth broad-leaved forest. If the remaining old-growth broad-leaved forest were to be converted to coniferous plantation, species that inhabit old-growth forest may become extinct.     

中国特有珍稀濒危植物猪血木的研究进展

对我国特有珍稀濒危植物猪血木的分类地位、资源现状及分布、生物学和生态学特性、发育生物学、保护遗传学、繁殖生物学、和濒危机制进行了综述,为该物种的种群恢复研究提供了参考.     

Common and Uncommon Understory Species Differentially Respond to Restoration Treatments in Ponderosa Pine/Douglas-Fir Forests, Montana

Restoration treatments have been widely advocated to address declining conditions in Pinus ponderosa forests throughout the western United States. However, few studies have examined treatment effects on individual plant species or whether responses differ for common species and uncommon species (those with low abundance in the community)—information that may be critical in managing for long‐term biodiversity. We investigated understory species responses to restoration treatments in ponderosa pine/Douglas‐fir forests using a randomized block experimental design with three blocks and four treatments (control, burn‐only, thin‐only, and thin‐burn). Understory vegetation was sampled before treatment and for three consecutive years after treatment. We used richness and an index of uniqueness to compare responses of common and uncommon native understory species among treatments, and indicator species analysis to identify individual species that responded to each treatment. Treatments that included thinning had significantly more unique species assemblages than the control. The thin‐only treatment increased common native species richness, whereas all active treatments significantly increased uncommon native species richness over the control, especially the thin‐burn. Generally, life‐forms did not explain the responses of individual species, though in the final sampling year several graminoids were exclusively indicative of treatments that included thinning. Very few species had reduced abundance in the thinning and burning treatments by the final sample year, whereas many uncommon and short‐lived species benefited from active treatments, especially the combined thin‐burn treatment. Active restoration treatments in these forests may foster plant diversity by minimally impacting common species while significantly benefiting disturbance‐dependent native species.     

基于通量和光谱观测的中亚热带人工针叶林光能利用效率的反演

利用光谱反射率测量的光化学植被指数（PRI）估算植被光合作用的光能利用效率（LUE）,能够更好地为生态系统总初级生产力的估算及尺度扩展提供重要的技术支撑.本研究以中国通量网（ChinaFLUX）千烟洲通量观测站为研究区域,2013年9月和12月在通量塔上测量了中亚热带人工针叶林的植被反射光谱,并获取了通量塔上同步观测的气象数据和涡度相关通量数据,对两者进行回归分析.结果表明： PRI-LUE相关关系（R²=0.20,P<0.001）优于NDVI LUE.在整个观测期内,土壤水分含量（SWC）与PRI组合的二元回归模型能够提高LUE的估算精度（日间观测R²=0.29,P<0.001;正午观测R²=0.30,P<0.01）,而在秋季,饱和水汽压差（VPD）与PRI组合的二元回归模型能较好地估算正午LUE（R²=0.448, P<0.001）,表明环境因子SWC和VPD是影响PRI-LUE关系的重要因素,不同季节的二元回归模型所选择的最佳环境变量有所不同.     

稀土元素镧和铈对冬凌草再生植株生长及次生代谢产物的影响

以冬凌草无菌苗为材料,在冬凌草再生植株时期,添加不同浓度的稀土元素镧和铈,用重量法测定其单株平均鲜重及干重,用高效液相法测定冬凌草甲素、乙素、迷迭香酸的含量,参考农作物、园艺作物种质评比的方法,根据冬凌草生产中各项指标的重要性,设置权重,计算加权后得到综合评分对其进行综合评价,探讨稀土元素镧、铈对冬凌草再生植株产量及次生代谢产物冬凌草甲素、乙素、迷迭香酸含量的影响。结果表明:空白对照组综合评分为62.99分,添加稀土元素铈的条件下,1μmol·L-1Ce Cl3·7H2O评分最高为87.96分,添加稀土元素镧的条件下,5μmol·L-1La Cl3·6H2O评分最高为74.44分,这表明Ce Cl3·7H2O对冬凌草再生植株生长及次生代谢产物积累的促进作用优于La Cl3·6H2O;适宜浓度的镧、铈能促进冬凌草再生植株的生长及次生代谢产物冬凌草甲素、冬凌草乙素、迷迭香酸的合成,而高浓度10μmol·L-1La Cl3·6H2O具有抑制的情况。该研究结果将对进一步研究稀土元素对冬凌草再生植株生长的促进作用机制奠定基础,为植物组织培养中如何科学合理地使用稀土元素提供理论依据。     

美国孤儿药开发的政策、策略与实践

简述了罕见病及孤儿药的定义和研发意义,重点介绍了美国针对孤儿药开发的现有制度法规、激励政策及管理经验,并以实例 分析从研发、注册和上市等角度探讨了美国孤儿药开发的策略,旨在为从事孤儿药开发工作的人士提供参考。     

Mismatch in the distribution of floral ecotypes and pollinators: insights into the evolution of sexually deceptive orchids

Plants are predicted to show floral adaptation to geographic variation in the most effective pollinator, potentially leading to reproductive isolation and genetic divergence. Many sexually deceptive orchids attract just a single pollinator species, limiting opportunities to experimentally investigate pollinator switching. Here, we investigate Drakaea concolor, which attracts two pollinator species. Using pollinator choice tests, we detected two morphologically similar ecotypes within D. concolor. The common ecotype only attracted Zaspilothynnus gilesi, whereas the rare ecotype also attracted an undescribed species of Pogonothynnus. The rare ecotype occurred at populations nested within the distribution of the common ecotype, with no evidence of ecotypes occurring sympatrically. Surveying for pollinators at over 100 sites revealed that ecotype identity was not correlated with wasp availability, with most orchid populations only attracting the rare Z. gilesi. Using microsatellite markers, genetic differentiation among populations was very low (G_ST = 0.011) regardless of ecotype, suggestive of frequent gene flow. Taken together, these results may indicate that the ability to attract Pogonothynnus has evolved recently, but this ecotype is yet to spread. The nested distribution of ecotypes, rather than the more typical formation of ecotypes in allopatry, illustrates that in sexually deceptive orchids, pollinator switching could occur throughout a species' range, resulting from multiple potentially suitable but unexploited pollinators occurring in sympatry. This unusual case of sympatric pollinators highlights D. concolor as a promising study system for further understanding the process of pollinator switching from ecological, chemical and genetic perspectives.     

Pollen source affects female reproductive success and early offspring traits in the rare endemic plant Polemonium vanbruntiae (Polemoniaceae)

Understanding the relative magnitudes of inbreeding and outbreeding depression in rare plant populations is increasingly important for effective management strategies. There may be positive and negative effects of crossing individuals in fragmented populations. Conservation strategies may include introducing new genetic material into rare plant populations, which may be beneficial or detrimental based on whether hybrid offspring are of increased or decreased quality. Thus, it is important to determine the effects of pollen source on offspring fitness in rare plants. We established pollen crosses (i.e. geitonogamous‐self, autonomous‐self, intrasite‐outcross, intersite‐outcross and open‐pollinated controls) to determine the effects of pollen source on fitness (seeds/fruit and seed mass) and early offspring traits (probability of germination, number of leaves, leaf area and seedling height) in the rare plant Polemonium vanbruntiae. Open‐pollinated, intrasite‐outcross and geitonogamous‐self treatments did not differ in fitness. However, plants receiving autonomous‐self pollen had the lowest fitness and the lowest probability of seed germination. Intersite‐outcross plants contained fewer seeds/fruit, but seeds germinated at higher frequencies and seedlings were more vigorous. We also detected heterosis at the seed germination stage. These data may imply that natural populations of P. vanbruntiae exhibit low genetic variation and little gene flow. Evidence suggests that deleterious alleles were not responsible for reduced germination; rather environmental factors, dichogamy, herkogamy and/or lack of competition among pollen grains may have caused low germinability in selfed offspring. Although self‐pollination may provide some reproductive assurance in P. vanbruntiae, the result is a reduction in germination and size‐related early traits for selfed offspring.     

Fluorescence emission mechanism and fluorescence properties of ternary Tb(III) complex with diphenyl sulphoxide and bipyridine

A novel ternary complex, TbL₅L′(ClO₄)₃·3H₂O, two binary complexes, TbL₇(ClO₄)₃·3H₂O and TbL′_3.5(ClO₄)₃·4H₂O has been synthesized (using diphenyl sulphoxide as the first ligand L, bipyridine as the second ligand L′). Their composition was analysed by element analysis, coordination titration, IR spectra and ¹H‐NMR, and the fluorescence emission mechanism, fluorescence intensities and phosphorescence spectra were also investigated by comparison. It was shown that the ternary rare‐earth complex showed stronger fluorescence intensities than the binary rare‐earth complexes in such material. The strongest characteristic fluorescence emission intensity of the ternary system was 8.23 times, 3.58 times as strong as that of the binary systems TbL₇(ClO₄)₃·3H₂O and TbL′_3.5 (ClO₄)₃·4H₂O, respectively. By fluorescence analysis it was found that both diphenyl sulphoxide and bipyridine could sensitize the fluorescence intensities of rare‐earth ions. In particular, in the ternary rare‐earth complex, introduction of bipyridine was of benefit to the fluorescence properties of Tb(III). Copyright © 2011 John Wiley & Sons, Ltd.