基于智能体模型的青岛市林地生态格局评价与优化

设计并在GIS平台上开发了基于智能体的生态格局评价模型,以青岛市及周边地区林地为研究对象,分析不同林地空间格局及生态网络保护框架对于物种生存与扩散的影响.结果表明,与现状相比,不同等级的生态网络框架对物种种群数量与物种迁移都有明显提升,且等级越高的生态网络框架提升作用越明显.然而仅仅依靠生态网络框架不足以使研究区域林地系统形成功能上的相互连通,因此,在分析研究区域现状土地利用格局基础上,提出与湿地系统结合,在胶州湾周围及大沽河干流地区增加林地的空间布局.通过模型模拟分析,发现优化后的林地空间格局结合生态网络框架能有效提升林地之间的物种扩散.基于模拟结果,为研究区林地生态格局构建提出如下建议:(1)保证现有的规模较大的林地不被破坏;(2)青岛市中部湿地系统可以作为新增林地的理想区域;(3)生态网络框架可作为青岛市建立城市组团间生态间隔的空间参考.     

柠条锦鸡儿籽油体外抗真菌作用及其机制研究(英文)

参照美国临床实验室标准化委员会(NCCLS)推荐的《产孢丝状真菌的液基稀释法抗真菌药物敏感性试验方案》(M38-A),测定超临界CO2萃取的柠条锦鸡儿籽油对3种(每种15株)临床常见的皮肤癣菌的最低抑菌浓度(MIC);高效液相色谱法研究柠条锦鸡儿籽油对真菌细胞膜麦角甾醇生物合成的影响以探讨其作用机制。结果表明柠条锦鸡儿籽油对犬小孢子菌、须癣毛癣菌、红色毛癣菌的MIC范围分别为64～512μg/mL、32～512μg/mL、64～1024μg/mL;高效液相色谱法检测显示,与其生长对照菌相比,籽油作用的皮肤癣菌细胞膜上麦角甾醇含量明显降低,且具有剂量依赖性。柠条锦鸡儿籽油主要是通过影响真菌细胞膜上麦角甾醇的合成而发挥抗真菌作用。     

Detecting un-authorized genetically modified organisms (GMOs) and derived materials

Genetically modified plants, in the following referred to as genetically modified organisms or GMOs, have been commercially grown for almost two decades. In 2010 approximately 10% of the total global crop acreage was planted with GMOs (James, 2011). More than 30 countries have been growing commercial GMOs, and many more have performed field trials. Although the majority of commercial GMOs both in terms of acreage and specific events belong to the four species: soybean, maize, cotton and rapeseed, there are another 20 + species where GMOs are commercialized or in the pipeline for commercialization. The number of GMOs cultivated in field trials or for commercial production has constantly increased during this time period. So have the number of species, the number of countries involved, the diversity of novel (added) genetic elements and the global trade. All of these factors contribute to the increasing complexity of detecting and correctly identifying GMO derived material. Many jurisdictions, including the European Union (EU), legally distinguish between authorized (and therefore legal) and un-authorized (and therefore illegal) GMOs. Information about the developments, field trials, authorizations, cultivation, trade and observations made in the official GMO control laboratories in different countries around the world is often limited, despite several attempts such as the OECD BioTrack for voluntary dissemination of data. This lack of information inevitably makes it challenging to detect and identify GMOs, especially the un-authorized GMOs. The present paper reviews the state of the art technologies and approaches in light of coverage, practicability, sensitivity and limitations. Emphasis is put on exemplifying practical detection of un-authorized GMOs. Although this paper has a European (EU) bias when examples are given, the contents have global relevance.     

Variation of B Chromosome Associated with Tissue Culture in Wheat-rye Cross

In vitro variation of B chromosomes was studied by examining the callus cells derived from the immature embryos from a cross of Chinese Spring wheat ( Triticum aestivum L.) and Fin 7416 rye ( Secale cereale L.) carrying two B chromosomes. In 40-d-old callus cells, the numbers of B chromosomes ranged from one to four in 65.6% of the cells observed. The distribution of B chromosome numbers was associated with the ploidy levels of the normal chromosomes (A chromosomes). The frequency of the cells with high numbers of B chromosomes (i.e., three or four B chromosomes) in the amphiploid cells with 56 A chromosomes was greater than those in the haploid cells with 28 A chromosomes. Although structural changes in the rye A chromosomes were observed, cytological observation and genomic in situ hybridization demonstrated that the rye B chromosomes were conserved in morphological appearance following tissue culture.     

Photosynthetic CO2 affinity of the aquatic carnivorous plant Utricularia australis (Lentibulariaceae) and its investment in carnivory

Aquatic carnivorous plants usually grow in shallow dystrophic waters poor in inorganic N and P. Utricularia australis was chosen as a model plant for its prolific distribution and great ecological plasticity. The photosynthetic CO₂ compensation point and factors associated with investment in carnivory and capture of prey were measured in 17 U. australis micropopulations in Třeboň basin, Czech Republic, together with water chemistry factors at these sites differing greatly in their trophic level, water hardness, and prey availability. Apical shoot growth rate was estimated at some oligotrophic sites. The micropopulations differed greatly in the proportion of traps with animal prey (2.7–70%, mean 26%), trap proportion to total biomass (1.4–42%, mean 26%), mean trap biomass (0.7–63 μg trap⁻¹, mean 19 μg), and maximum trap size (1–3 mm, mean 2.0 mm). CO₂ compensation points ranged from 0.7 to 6.1 μM (mean 2.6 μM). A weak HCO₃ ⁻ use (compensation point 0.51 mM) was found in plants growing in alkaline water. Trap biomass proportion did not correlate significantly with prey capture and CO₂ compensation points with ambient [CO₂]. A very rapid apical growth (2.5–4.2 new nodes day⁻¹) occurred in sand pits. Thus, HCO₃ ⁻ use in U. australis can be induced by growing at very high pH. CO₂ compensation points resembled those known in other aquatic non-carnivorous plants. They did not reflect carnivory. In spite of very rapid apical shoot growth, the relative growth rate of U. australis can be zero in oligotrophic habitats without prey.     

内蒙古锡林河流域三种草原蝗虫对植物高度选择的观察

在实验条件下,观察了发生期及个体大小不一致的3种草原蝗虫对植物高度选择情况．结果表明：蝗虫对植物高度的选择与其本身发生时期及个体大小相关,是物种长期进化的结果,同时,还探讨了蝗虫对植物高度的选择与温度、温度及光照强度之间的关系．     

The trophic impact of small mammals in successional grasslands

The habitat use and diets of small mammals inhabiting grassland plots of different successional ages were investigated by live-trapping and faecal analysis over a period of 16 months. The contribution of the major plant life forms and the structural profile of the vegetation of each plot and the availability of insect prey were assessed. The dominant species of small mammal found on each plot were Sorex araneus, S. minutus, Apodemus sylvaticus and Microtus agrestis . Small mammals were most commonly found in the late and mid-successional stages, reflecting the habitat structure and food availability. A wide range of insects and other invertebrates were eaten by all four species and insects formed 50–62% of the animal prey taken. The incidence of certain prey in the diets differed between plots. The daily consumption rate of invertebrates by shrews and mice was estimated at some 6800 prey per ha. The greatest predatory impact came from shews but A. sylvaticus showed increased consumption of invertebrates in spring. The combined predatory impact of the grassland small mammal community on insect populations alone was estimated to average 0.01% per day and is predicted to be greatest in the mid-successional stages.     

Chromium in plants

Chromium is an essential trace element and is associated with some biological pathways, especially with glucose tolerance. For these reasons, we decided to determine the concentration of chromium in two sets of Brazilian medicinal plants. The first group consisted of plants that are considered as antidiabetic, whereas the second included plants that do not have this therapeutic property. The concentration of chromium was determined by flameless atomic absorption. All the plants analyzed contain chromium in the normal range for this element, but the hypoglycemic plants contain more chromium than the others (1–4 μg/g compared to 0.5–1.5 μg/g).