三江源自然保护区森林-草甸交错带植物优先保护序列研究

运用系统分析方法和原理,在资料收集和实地调查的基础上,借助专家咨询系统构建了三江源自然保护区森林一草甸交错带植物受威胁等级、优先保护定量分级评价指标体系以及相应的定量评价标准．评价体系包括物种濒危系数、遗传损失系数和利用价值系数3个评价系统层和10个评价指标层．利用专家咨询法和层次分析法,定量确定各个系统层和指标层的权重．通过数学模型和计算机程序计算,分别度量了三江源自然保护区森林．草甸交错带植物物种受威胁状况和优先保护序列状况的濒危系数和优先保护系数;对照植物濒危等级和优先保护序列区域性评价标准,定量评价了植物物种濒危等级和优先保护等级．评价结果表明,三江源自然保护区森林．草甸交错带的种子植物有濒危种4种,脆弱种68种,敏感种179种,安全种695种;该地区种子植物一级保护物种8种,二级保护物种78种,三级保护物种164种。暂缓保护物种696种．最后,针对植物物种优先保护序列评价的指标体系与权重分配问题。物种濒危等级与优先保护序列之间的关系,物种濒危等级评价的空间尺度问题进行了分析和探讨。     

一株具有广谱抗菌活性小单孢菌的分离和鉴定

从南昌瑶湖的农田土壤样品中分离到一株具有广谱抗菌活性的稀有放线菌。通过形态特征、培养特征、生理生化特性、细胞化学成分及16S rRNA基因序列等多相分类特征研究, 将该稀有放线菌鉴定为炭样小单孢菌。     

江西三清山珍稀濒危植物考察研究

三清山有珍稀濒危植物33种,隶属30属22科,其中蕨类植物1科1属1种,裸子植物6科12属12种;被子植物15科17属20种。主要讨论了三清山珍稀濒危植物地理分布及保护。     

稀土对蚯蚓体内氨基酸含量的影响

采用滤纸接触染毒法,分别进行了氯化稀土、氯化镧与土居动物蚯蚓接触染毒不同时间和不同浓度的试验。研究其对蚯蚓体内氨基酸含量的影响变化。结果表明。Re、La对蚯蚓体内的氨基酸含量影响较显著,在低浓度时总体表现为促进蚯蚓体内氨基酸的形成,而在高浓度状态下则使蚯蚓体内氨基酸含量下降,产生抑制作用,两种稀土在400mg·L^-1浓度时,蚯蚓体内氨基酸含量除脯氨酸外开始上升,随着作用时间延长,氨基酸含量逐渐下降,在100～1200mg·L^-1浓度范围,两种稀土均引起蚯蚓体内脯氨酸含量的下降,产生抑制作用。     

An integrative approach for the conservation and management of South Africa's floristic diversity at the provincial level

As a party to the Convention on Biological Diversity (CBD), South Africais obliged to ensure that CBD objectives are met. Fundamental to the concept ofbiodiversity are the different levels of biological organization ranging fromlandscapes to genes. Historically, biodiversity conservation has predominantlyfocussed on species, while southern African nature reserves were generally notestablished with biodiversity criteria under consideration. This paper describesan integrative approach to conserving and managing all levels of biodiversity inGauteng, the smallest province in South Africa. Utilizing land cover andvegetation maps for the province, higher level biodiversity considerations willincorporate principles of landscape ecology together with gap analysis anditerative techniques, while lower level biodiversity considerations will involvethe assessment of the status and distribution of Red Data plant species in theprovince. As the final output, a map will be created within a GeographicInformation System depicting priority conservation areas with associated broadmanagement recommendations. A landscape mosaic with simple management guidelinesfor landowners will attempt to facilitate the conservation of landscapeprocesses.     

Role of antioxidant defense system and biochemical adaptation on stress tolerance of high mountain and steppe plants

Plants growing in small fragmented populations under stressful environmental conditions may have reduced sexual reproduction. This can cause low gene flow between populations and eventually extinction. Here we report on a pollination experiment with Sorbus torminalis, a rare fleshy-fruited tree with a submediterranean distribution in Europe. At the northern limit of its range in SE-Denmark two relatively small and isolated populations were studied for effects of seven pollination treatments on fruit production and on the timing of fruit abortion. There was evidence that lack of pollination and spontaneous self-pollination caused particularly high fruit abortion, which indicates that apomixis is unlikely and spontaneous self-pollination not efficient. Fruit abortion was delayed after hand pollination, which suggests limitation by pollen quantity. Self-pollination caused earlier abortion than experimental cross-pollination within or between populations indicating inbreeding depression. There was no evidence for outbreeding depression as measured by fruit abortion. We conclude that generative reproduction of S. torminalis is reduced on its northern distribution limit and that it might be negatively affected by pollen limitation and inbreeding effects, which have not been compensated for by increased self-compatibility or apomixis.     

Analysis of case-control age-at-onset data using a modified case-cohort method

Case-control designs are widely used in rare disease studies. In a typical case-control study, data are collected from a sample of all available subjects who have experienced a disease (cases) and a sub-sample of subjects who have not experienced the disease (controls) in a study cohort. Cases are oversampled in case-control studies. Logistic regression is a common tool to estimate the relative risks of the disease with respect to a set of covariates. Very often in such a study, information of ages-at-onset of the disease for all cases and ages at survey of controls are known. Standard logistic regression analysis using age as a covariate is based on a dichotomous outcome and does not efficiently use such age-at-onset (time-to-event) information. We propose to analyze age-at-onset data using a modified case-cohort method by treating the control group as an approximation of a subcohort assuming rare events. We investigate the asymptotic bias of this approximation and show that the asymptotic bias of the proposed estimator is small when the disease rate is low. We evaluate the finite sample performance of the proposed method through a simulation study and illustrate the method using a breast cancer case-control data set.     

A PCR-based method for detecting the mycelia of stipitate hydnoid fungi in soil

To reduce the reliance on sporocarp records for conservation efforts, information on the below-ground distribution of specific fungal species, such as stipitate hydnoid fungi, is required. Species-specific primers were developed within the internal transcribed spacer (ITS1 and ITS2) regions for 12 hydnoid fungal species including Bankera fuligineoalba, Hydnellum aurantiacum, H. caeruleum, H. concrescens, H. ferrugineum, H. peckii, Phellodon confluens, P. melaleucus, P. niger, P. tomentosus, Sarcodon glaucopus and S. squamosus. The specificity of the primer pairs was tested using BLAST searches and PCR amplifications. All primers amplified DNA only of the target species with the exception of those designed for P. melaleucus. In order to assess the ability of the primers to detect DNA from mycelium in soil, DNA extracted from soil samples taken from around solitary H. peckii sporocarps was amplified with the H. peckii primer 1peck and ITS2. H. peckii DNA was detected in 70% of all soil samples and up to 40 cm away from the base of individual sporocarps. The development of these species-specific primers provides a below-ground alternative for monitoring the distribution of these rare fungi.     

The impact of flooding and drought on seeds of Cnidium dubium, Gratiola officinalis, and Juncus atratus, three endangered perennial river corridor plants of Central European lowlands

The effects of flooding and drought on the post-flooding survival and germinability of seeds in the soil were investigated for three endangered river corridor angiosperms Cnidium dubium (Schkuhr) Thell., Gratiola officinalis L. and Juncus atratus Krocker. Freshly matured seeds were placed in small nylon bags and were buried in pots filled with soil collected from a wetland along the Lower Havel River. The pots were subjected to different winter/spring flooding treatments (30, 60, 120, and 180 days) and to drought for up to 3 years. Every year in spring, after drawdown, the seeds were exhumed, counted and tested for germination. Seed mortality of flooded seeds was low, except for C. dubium. Flooding did not affect germination of seeds of J. atratus. Flooding of seeds of C. dubium and G. officinalis had inconsistent, but no beneficial effects on germination of either. The year of harvest and the interannual variability of weather are found to be the main factors affecting germinability of C. dubium and G. officinalis in the course of the three consecutive years.The experiment showed that the capacity of the flooded seed bank to maintain germination ability and viability for extended periods of time could be directly related to the flooding duration of natural habitats of the three species. The three species are resilient to variable flooding. Seeds appeared desiccation tolerant, and single flooding events do not deplete their seed bank.     

The potencial role of rare earths in the pathogenesis of interstitial lung disease: a case report of movie projectionist as investigated by neutron activation analysis

A 60-year-old male subject who worked as a movie projectionist and who was exposed for 12 years to rare earths (RE) containing dusts from cored arc light carbon electrodes was investigated. Chest X-ray films and pulmonary function tests showed an interstitial lung disease, emphysema and a severe obstructive impairment with marked decrease of carbon monoxide diffusion capacity. The histological examination of a transbronchial biopsy confirmed the diffuse interstitial lung fibrosis. Neutron activation analysis (NAA) of the biopsy showed concentrations of cerium (Ce), lanthanum (La), neodimium (Nd), samarium (Sm), terbium (Tb) and ytterbium (Yb) which were high compared to the corresponding elements in the transbronchial biopsies of 5 unexposed subjects as a control group. Thorium (Th) (which is generally present as an impurity of the RE compounds) was also determined in order to estimate the radiation dose in the lung of the worker.

On the basis of the clinical observations, of the analytical results by neutron activation analysis of RE and of the presence of Th in the transbronchial biopsy, as well as of the differential diagnosis, which tended to exclude other occupational or non-occupational lung diseases, a relation between the observed interstitial lung fibrosis and occupational exposure to RE is highly probable.