稀土叶面肥对葡萄园节肢动物群落和食饵功能团的影响

为阐明稀土叶面肥对江淮丘陵和黄河故道葡萄园节肢动物群落、中性昆虫亚群落和食饵功能团组成的影响,通过系统调查和数学分析得出,稀土元素镧、钕和醋(CK2)对肥东葡萄园节肢动物总群落、植食性昆虫亚群落和捕食性天敌亚群落的物种数、个体数和物种丰富度的影响均不显著。稀土叶面肥对萧县总群落的物种数影响显著,镧对总群落物种丰富度影响显著,其余影响不显著。镧和钕元素对两地葡萄园中性昆虫亚群落的物种数和物种丰富度影响极显著,对个体数影响不显著,CK2对中性昆虫亚群落的物种数、个体数和物种丰富度影响均不显著;肥东县葡萄园镧肥区、钕肥区和CK2与CK1之间食饵功能团物种数的t值为3.4384、2.3911和2.0528,镧肥区和钕肥区与CK2之间食饵功能团物种数的t值为1.6397和0.6357;萧县葡萄园镧肥区、钕肥区和CK2与CK1之间食饵功能团的物种数t值为2.2909、2.3223和0.3674,镧肥和钕肥区与CK2之间的t值为2.7533和2.7744,表明镧肥和钕肥对两地食饵功能团的物种数影响均显著。肥东县镧肥区、钕肥区和CK2与CK1之间食饵功能团的个体数t值为1.3047、1.0338和0.2300,镧肥区和钕肥区与CK2之间的t值为1.6014和1.1835;萧县镧肥区、钕肥区和CK2与CK1之间食饵功能团的个体数t值为1.0431、1.0245和0.7369,镧肥区和钕肥区与CK2之间的t值为0.9495和0.9490;两地处理与与CK1和CK2之间食饵功能团的个体数t值均小于t0.05,表明稀土叶面肥对两地食饵功能团个体数影响不显著。稀土叶面肥对肥东葡萄园食饵功能团物种丰富度影响很小,萧县镧肥和钕肥与CK2之间物种丰富度的t值为2.1709和2.0226,差异显著。综上所述,稀土叶面肥对葡萄园中性昆虫亚群落和食饵功能团的物种数影响显著。     

城市周边农田景观中非农生境与土壤动物的协同关系——以沈阳市沈北新区为例

农田景观中非农生境对生物多样性保护、耕地多功能性和农业产量等具有重要影响.本文选择中国城市化过程中生物多样性保护与农业高产需求相互冲突的典型地区沈阳市沈北新区为研究区,采用信息熵模型划分为城市近郊、城市边缘区和乡村区域,采用手捡法和Baermann 法调查,鉴定了节肢动物和土壤线虫,并通过线性回归分析确定了非农生境类型、结构及数量与土壤动物的协同关系.结果表明： 沈北新区农田景观的非农生境斑块面积均小于1 hm².随着与城市中心距离的增加,非农生境类型和比例逐渐增加,面积比例呈倒“U”型变化,斑块数量比例从8.6%增加到27.8%;土壤动物个体数呈现“U”型变化,物种量无明显变化规律.乡村和城市近郊的非农生境斑块数量比与土壤动物个体数呈正向协同关系,城市边缘区无明显规律;非农生境面积比与土壤动物个体数均呈反向协同关系;非农生境斑块数量比和面积比与土壤动物物种量均无明显协同关系.     

我国8种猛禽的DNA条形码技术研究

用DNA条形码通用引物扩增了我国8种猛禽(14只个体)的线粒体细胞色素c氧化酶亚基I(COI)基因,选取648 bp DNA条形码标准区域,结合99条猛禽条形码序列,探讨DNA条形码对猛禽的识别和鉴定.结果显示,75.6%的猛禽符合10×规则,且80.5%的猛禽均具有独特的DNA条形码可作为物种鉴定的依据,另有19.5%的猛禽(鵟属8种猛禽)由于种间差异太小,DNA条形码对它们的识别鉴定存在一定局限.     

棉田生态系统中害虫、天敌群落结构与功能关系的研究

为探讨生物群落结构与功能的关系,有效地开展棉田害虫、天敌的生态调控,作者在系统调查与测定华北棉区８种不同时空类型棉田害虫、天敌群落物种丰富度、总个体数、能流量多样性指数及群落生产力的基础上,分析了各类型棉田害虫、天敌群落结构与功能的关系,总结了如下的一般规律：１）上一营养层（棉株或害虫）的生产力越高,其所支持的下一营养层（害虫或天敌）群落的总个体数和生产力增加;２）害虫群落的物种丰富度与其群落生产     

基于标准化降水蒸散指数的川西高原干旱时空变化

干旱是川西高原具有一定破坏力的自然灾害,研究其时空变化对该区抗旱防灾、保障农业生产安全、维持生态系统健康具有重要的现实意义。本研究基于川西高原1980—2020年48个气象站点的逐日气象数据,利用Penman-Monteith模型计算潜在蒸散量和标准化降水蒸散指数(SPEI),通过线性倾向分析、干旱特征分析方法对川西高原干旱时空特征进行分析。结果表明：1980—2020年,川西高原年尺度和春季尺度SPEI呈弱湿润化趋势,夏秋冬季呈干旱化趋势,研究区西南部的山地及东北部的草原为易旱区。研究区年际干旱影响范围弱增,除春季为减少趋势外,夏秋冬季的干旱影响范围均呈增加趋势。全区干旱频率整体偏高,干旱低频区主要位于川西西部和东北部的部分地区,其余均为高频区。     

北京地区隼形目鸟类物种多样性现状调查

为有效保护珍稀野生动物多样性,于2001～2005年利用固定样线法对北京地区隼形目猛禽物种和生态分布进行了调查,获得珍稀鸟类14种,其中国家一级保护物种为金雕和白肩雕.与历史纪录比较分析了物种数量发展趋势,依据观察记录时间讨论了居留型的变化特点,结合猎物资源和生态旅游开发现状提出了促进猛禽种群恢复的对策.     

白僵菌超低容量油剂林间应用对生物多样性的影响

2001～2003年在福建省云霄县进行了白僵菌超低容量油剂林间防治马尾松毛虫后对生物多样性的影响研究(包括使用前后的物种丰富度S、个体数N、多样性指数H'、均匀度指数R和优势度指数D等).结果表明,未防治区和白僵菌油剂防治区的物种数分别为473种和392种,而化学防治区的物种数只有266种;白僵菌油剂防治区天敌和害虫个体数与未防治区的比例相近,分别为0.1049:1和0.1051:1,明显高于化学防治区(0.0558:1);化学防治和白僵菌油剂防治均降低了物种的丰富度和多样性,同时也增强了物种的优势度,但化学防治区与未防区的差异显著,白僵菌油剂防治区与未防区的差异不显著,尤其对天敌和非目标昆虫无显著影响.     

大理洱海西岸农耕区鸟类多样性

2011年在大理洱海西岸农耕区选择5片调查样区,每个样区布设1条调查样线,采用不定宽样线法对鸟类物种和数量及其栖息生境进行了4个季节的观察记录,共记录鸟类87种,隶属11目25科。研究结果表明秋季鸟类多样性最高;不同生境类型中,防护林内的鸟类多样性最高。以小时为单位统计每小时遇见鸟类个体数,春季为70.71只,夏季为79.36只,秋季为76.65只,冬季为70.37只。     

白僵菌超低容量油剂林间应用对生物多样性的影响

2001～2003年在福建省云霄县进行了白僵菌超低容量油剂林间防治马尾松毛虫后对生物多样性的影响研究(包括使用前后的物种丰富度S、个体数N、多样性指数H'、均匀度指数R和优势度指数D等),结果表明,未防治区和白僵菌油剂防治区的物种数分别为473种和392种,而化学防治区的物种数只有266种;白僵菌油剂防治区天敌和害虫个体数与未防治区的比例相近,分别为0．1049：1和0．1051：1．明显高于化学防治区(0．0558：1);化学防治和白僵菌油剂防治均降低了物种的丰富度和多样性。同时也增强了物种的优势度,但化学防治区与未防区的差异显著,白僵菌油剂防治区与未防区的差异不显著,尤其对天敌和非目标昆虫无显著影响。     

吡虫啉对烟田节肢动物群落的影响研究

利用群落参数分析了吡虫啉对烟田节肢动物群落及其各亚群落的影响。结果表明,施药后对烟田节肢动物群落、害虫亚群落的物种数有一定的影响,对天敌昆虫和蜘蛛亚群落物种数的影响不明显。5月23日施药后至6月13日施药区(Ⅱ)和对照区节肢动物群落、害虫亚群落个体数均下降,下降程度施药区大于对照区。6月14日施药后施药区节肢动物群落、害虫亚群落个体数下降,对照区显著上升。两次施药对天敌昆虫和蜘蛛亚群落个体数的影响不明显,施药后一段时间内优势种烟蚜种群个体数量显著下降,使节肢动物群落和害虫亚群落优势集中性下降,多样性指数和稳定性增加。     

Recent advances in the study of Kaposi's sarcoma-associated herpesvirus replication and pathogenesis

It has now been over twenty years since a novel herpesviral genome was identified in Kaposi's sarcoma biopsies. Since then, the cumulative research effort by molecular biologists, virologists, clinicians, and epidemiologists alike has led to the extensive characterization of this tumor virus, Kaposi's sarcoma-associated herpesvirus(KSHV; also known as human herpesvirus 8(HHV-8)), and its associated diseases. Here we review the current knowledge of KSHV biology and pathogenesis, with a particular emphasis on new and exciting advances in the field of epigenetics. We also discuss the development and practicality of various cell culture and animal model systems to study KSHV replication and pathogenesis.     

The structure, reproduction and taxonomy of Vidalia and Osmundaria (Rhodophyta, Rhodomelaceae)

Comprises species occurring mostly in subtidal habitats in tropical, subtropical and warm-temperate areas of the world. An analysis of the type species, V. spiralis (Sonder) Lamouroux ex J. Agardh, a species from Australia, establishes basic characters for distinguishing species in the genus. These characters are (1) branching patterns of thalli, (2) flat blades that may be spiralled on their axis, (3) width of the blade, (4) primary or secondary derivation of sterile and fertile branchlets and (5) position of sterile and fertile branchlets on the thalli. Application of the latter two characters provides an important basic method for separation of species into three major groups. Osmundaria , a genus known only in southern Australia, was studied in relation to Vidalia , and its separation from the Vidalia assemblage is not accepted. Species of Vidalia therefore are transferred to the older genus name, Osmundaria. Two new species, Osmundaria papenfussii and Osmundaria oliveae are described from Natal. Confusion in the usage of the epithet, Vidalia fimbriala Brown ex Turner has been clarified, and Vidalia gregaria Falkenberg, described as an epiphyte on Osmundaria pro/ifera Lamouroux, is revealed to be young branches of the host, Osmundaria prolifera.     

New or rare chromosome counts in Artemisia L. (Asteraceae, Anthemideae) and related genera from Kazakhstan

Fifteen chromosome counts of six Artemisia taxa and one species of each of the genera Brachanthemum, Hippolytia, Kaschgaria, Lepidolopsis and Turaniphytum are reported from Kazakhstan. Three of them are new reports, two are not consistent with previous counts and the remainder are confirmations of very scarce (one to four) earlier records. All the populations studied have the same basic chromosome number, x = 9, with ploidy levels ranging from 2x to 6x. Some correlations between ploidy level, morphological characters and distribution are noted.     

肝癌中HBV和HCV基因和抗原的分布及意义

采用原位分子杂交方法检测HCV RNA及HBV X基因;采用免疫组织化学方法研究HCV核心抗原,非结构区C33c抗原及HBxAg在肝细胞肝癌中的定位及分布.结果表明(1)HCV RNA、HBV X基因在肝细胞肝癌组织检出率分别为40%(55/136)和82%(112/136).HCV RNA定位于癌细胞的胞浆内,阳性细胞呈散在、灶状及弥漫分布三种形式;HBV X基因在肝癌细胞中的分布呈胞浆型、核型及核浆型,阳性细胞也呈上述三种分布形式;(2)HCV C33c抗原、核心抗原在肝细胞肝癌中的阳性率为81%(133/164)及86%(141/164).C33c抗原定位于癌细胞及肝细胞的胞浆内;核心抗原既定位于癌细胞核中,又可定位于胞浆中.C33c抗原阳性细胞以灶状分布为主;而核心抗原阳性细     

Selection with two alleles and complete dominance

For a plant selection model with frequency-independent viabilities, fertilities and selfing rates, it is shown that apart from global fixation, for certain parameter combinations a protected polymorphism and facultative fixation (either allele may become fixed according to initial frequencies) may both occur. Facultative fixation requires different selling rates for the dominant and recessive type. Protection of the polymorphism requires resource allocation for male and female function. In this connection the problem of purely genetically caused population extinction is discussed.
For general frequency dependence and regular segregation, the chances for establishment of a completely recessive gene are compared to those of a completely dominant gene. It is proven that the process of establishment of the recessive gene, despite a fitness advantage, may be considerably endangered by drift effects if random mating prevails. The recessive gene may reach the same effectivity in establishment as a dominant gene, only if the recessive homozygote mates exclusively with its own type during the period of establishment.