二级构筑水平上刺五加种群分布格局的研究

本文研究了刺五加无性系群团在群落中以及无性系小株在无性系内的分布格局,运用聚集强度指数分析了刺五加无性系种群在不同群落中的聚集性程度。     

氟化物对家蚕幼虫中肠(钙,镁)-三磷酸腺苷酶活性的影响

添食NaF抑制家蚕幼虫中肠(钙,镁)-三磷酸腺苷酶[(Ca~(2+),Mg~(2+))-ATPase]的活性。该抑制作用随添食NaF的浓度提高,或添食日数延长而增加,有累积效应。添食适量的CaCl_2或CaCl_2和Na_2ATP能降低NaF对(Ca~(2+),Mg~(2+))-ATPase活性的抑制。试验结果说明,应用Lee的(Ca~(2+),Mg~(2+))-ATPase动力学模型可获得满意的解释。氟化物抑制家蚕幼虫体内组织细胞膜上(Ca~(2+),Mg~(2+))-ATPasc活性,致使Ca~(2+)在蚕体内平衡失调,是家蚕氟中毒的一种重要的毒理学上的分子机制。     

Furobenzotropolones A,B and 3-Hydroxyepicoccone B with Antioxidative Activity from Mangrove Endophytic Fungus Epicoccum nigrum MLY-3

Three new metabolites, furobenzotropolones A, B (1–2) with unusual benzene and dihydrofuran moieties and 3-hydroxyepicoccone B (3), together with seven known compounds (4–10) were obtained from the endophytic fungus Epicoccum nigrum MLY-3 isolated from the fresh leaf of mangrove plant Bruguiear gymnorrhiza collected from Zhuhai. Their structures were assigned by the analysis of UV, IR, NMR, and mass spectroscopic data. Compound 1 was further confirmed by single-crystal X-ray diffraction experiment using Cu Kα radiation. In antioxidant activities in vitro, compounds 2, 3, 5, and 8 showed promising DPPH· scavenging activity with IC₅₀ values ranging from 14.7 to 29.3 µM. Compounds 2, 3, 5, 7, and 8 exhibited promising potent activity in scavenging ABTS· with IC₅₀ values in the range of 18–29.2 µM, which was stronger than that of the positive control ascorbic acid (IC₅₀ = 33.6 ± 0.8 µM).     

东北红豆杉种群结构与空间分布型的分析

本文研究了东北红豆杉种群的径级结构,高度结构和年龄结构,运用生命表描述了东北红豆杉种群动态的总趋势,判定了东北红豆杉种群分布格局的类型。     

Combining banker plants to achieve long-term pest control in multi-pest and multi-natural enemy cropping systems

Banker plants increase biological pest control by supporting populations of non-pest arthropod species, used as alternative hosts or prey by natural enemies. Due to the specificity of trophic interactions, banker plants may not efficiently promote natural enemies with different ecologies. Yet in most cropping systems, different pest species are present together and require different biocontrol agents to efficiently control them. In the present study, we tested the combined use of two banker plants and their associated prey/host to enhance populations of the specialist parasitoid Encarsia formosa targeting the main tomato pest Bemisia tabaci, and a polyphagous ladybird Propylea japonica targeting the secondary pest Myzus persicae in tomato crops. In a laboratory and a greenhouse experiment, we measured the abundances of these four species using the Ricinus communis—Trialeurodes ricini banker plant system alone, in combination with the Glycines max—Megoura japonica system, or in absence of banker plants. We found that the first banker plant system enhanced populations of E. formosa, resulting in increased suppression of B. tabaci populations and the suppression of their outbreak in both our laboratory and greenhouse experiment. Conversely, abundances of P. japonica were not affected by this first system, but were significantly increased when the second was present. This resulted in increased control of M. persicae populations and the suppression of their early and late outbreaks. Our study demonstrates the potential for combined banker plants to provide long-term, sustainable control of multiple pests by their target natural enemies in complex agroecosystems.

     

宁夏重点风沙区生态环境综合治理项目信息管理系统的开发与设计

宁夏重点风沙区生态环境综合治理项目是宁夏利用日本国际协力银行(JBIC)贷款开展沙漠化综合治理的一项重大工程：项目采用地理信息系统(GIS)、遥感(RS)和全球定位系统(GPS)等高新信息技术，实现了项目从规划设计到效益评估的全过程可视化和数字化管理。本文介绍了该项目信息管理系统开发与设计的技术平台选择、开发方法、技术路线、数据库结构设计、数据库管理、功能设计、操作界面设计等，详细论述了系统中不同比例尺图形数据、不同分辨率遥感影像数据、不同格式文本数据的建库技术和管理方式。根据系统的推广使用情况，本文最后分析了该系统与传统关系型数据库管理系统相比的优点以及该系统今后需要改进和完善的内容。     

SOME PROBLEMS OF DESERVED RESEARCH IN THE PROCESS OF GAS DESULPHATION

Many factors have influence on gas desulphation,Through theoretical a nalysisof desulphation reaction principle and a lot of experiment and production data,this paper studies withthe emphasis on how to solve some concrete problems about selecting and mixing desulphation solu-tion in order to gain the best economic benefits and environment benefits and social comprehensivebenefits.     

砂轮变速抑制磨削颤振的试验研究

通过试验研究，证明了在磨削过程中连续地改变砂轮转速具有较强的抑制磨削颤振的作用，是一种提高磨削表面质量的有效方法。通过单因素试验，研究了各种变速参数对抑振作用的影响，得出了一系列可供生产实际参考的数据和结论。     

影响大豆疫霉菌(PhytoPhthra sojae)卵孢子萌发的条件

培养1个月的大豆疫霉菌卵孢子在水琼脂或土壤薄膜上均可萌发,在水琼脂上萌发只形成芽管,在土壤薄膜上萌发形成芽管和孢子囊.卵孢子在两种基质上萌发最适温度为18-24℃.光照刺激卵孢子萌发,抑制孢子囊的形成.卵孢子萌发不需外源养分.不同菌株卵孢子萌发率差异较大.