浙江南部近海前肛鳗营养生态位变化研究——基于稳定同位素技术

基于2016年和2020年浙江南部近海收集的71尾前肛鳗样品,通过测定碳氮稳定同位素比值计算其营养生态位指标,对比分析前肛鳗不同发育过程、不同季节及不同年份营养生态位的差异,探究营养生态位的变动规律及对资源的利用情况。结果表明：（1）2016年和2020年前肛鳗平均δ¹³C值分别为（-15.19±0.31）‰、（-15.90±0.45）‰;平均δ¹⁵N值分别为（12.42±0.45）‰、（12.92±0.25）‰;（2）单因素方差分析表明,2016年前肛鳗不同发育过程δ¹³C值差异不显著（P>0.05）,δ¹⁵N值差异显著（P<0.05）,不同季节间δ¹³C值和δ¹⁵N值均存在显著差异（P<0.05）,而2020年前肛鳗不同发育过程δ¹³C值和δ¹⁵N值差异均不显著（P>0.05）,不同季节间δ¹³C值存在显著差异（P<0.05）,δ¹⁵N值差异不显著（P>0.05）;（3）从个体发育来看,2016年前肛鳗有向高营养级饵料生物摄食的趋势,而2020年前肛鳗摄食特化现象不明显,但均随个体发育过程生态位宽幅逐渐减小,表明个体发育过程营养生态位会出现资源竞争共存分化现象;（4）种群营养多样性指标结果显示前肛鳗在秋、冬两季食物来源较春、夏两季更广泛,春季营养多元化程度与秋季相似,夏季营养多元化程度与冬季相似,各季节间营养生态位重叠较小,存在明显的时间分化现象;（5）2020年前肛鳗种群营养结构多样性指标相比2016年均出现不同程度的降低,两年的SEAc未发生重叠现象。由于种内种间的竞争压力,研究发现前肛鳗在个体发育过程及不同时间段都出现了营养生态位分化现象,从而达到维持物种共存、保持食物网结构稳态的目的。     

基于稳定同位素技术的长湖鱼类营养结构研究

本研究应用碳、氮稳定同位素技术分析了2017年秋季（10月）和2018年春季（3月）湖北省荆州长湖鱼类营养结构特征,构建了δ¹³C和δ¹⁵N稳定同位素双位图,并计算了7个相关的量化指标。结果显示：所采集的16种鱼类,δ¹³C均值范围为（-27.7±0.8）‰~（-24.8±0.1）‰,δ¹⁵N的均值范围为（11.4±0.3）‰~（16.6±0.5）‰。营养生态位分析显示,长湖鱼类以偏肉食性鱼类黄颡鱼的营养级最高（3.28±0.2）,草鱼的营养级最低（1.74±0.1）。稳定同位素的量化指标表明,长湖春季鱼类群落核心生态位空间（standard ellipse area, SEA）、生态位总空间（total area, TA）和基础食物来源（δ¹³C range, CR）均高于秋季,两个季度的营养多样性（centrifugal distance, CD）和鱼类群落的整体密度（mean nearest neighbor distance, MNND）相似,但春季的营养长度（δ¹⁵N range, NR）和鱼类群落营养生态位分布范围（standard deviation of nearest neighbor distance, SDNND）值低于秋季。说明春季长湖的生态位总空间（TA上升）和基础食物来源（CR上升）较为丰富,但因鱼类种类的食性相近,其群落的总食物链降低（NR下降）。该研究可为分析拆围后长湖鱼类群落结构特征积累基础数据,也为长湖的渔业管理策略提供依据。     

基于稳定同位素技术的三峡库区短颌鲚营养生态位特征研究

为了预测三峡库区外来鱼类短颌鲚（Coilia nasus）在库区的种群发展趋势,评估其对库区水域生态系统的影响,基于碳氮稳定同位素技术,分析了三峡库区腹地,包括长江一级支流草堂河、大宁河,现有短颌鲚及杂食性和肉食性典型鱼类的营养级,在此基础上选择4种与短颌鲚营养级相近（包括太湖新银鱼Neosalanx taihuensis、翘嘴鲌Culter alburnus、鳡Elopichthys bambusa、大眼鳜Siniperca kneri）,及1种食谱存在较大重叠的鱼类（即鳙Aristichthys nobilis）,探讨了其营养生态位特征。结果显示,三峡库区短颌鲚δ¹⁵N值分布范围为12.112‰-14.497‰,营养级为3.762±0.196（Mean±SD）,低于太湖新银鱼,并高于大眼鳜、翘嘴鲌、鳡及鳙;三峡库区短颌鲚δ¹³C值分布范围为-27.236‰- -22.952‰,变幅低于鳙,高于太湖新银鱼、大眼鳜、翘嘴鲌及鳡,δ¹³C值分布频率呈单峰型与太湖新银鱼高度接近,表明短颌鲚在该水域食性广泛,且与太湖新银鱼的摄食偏好趋近。据此推测三峡库区短颌鲚营养级较高的主要原因是短颌鲚在三峡库区食物来源广泛,决定其富集¹⁵N途径可能更丰富。此外,营养生态位分析结果显示三峡库区短颌鲚营养生态位宽幅低于鳡、鳙,高于太湖新银鱼、翘嘴鲌、大眼鳜,据此推测三峡库区短颌鲚对饵料需求的特化程度可能不高,从营养角度对环境的适应性较强;且其与营养级相近鱼类的营养生态位重叠程度较低,存在明显的营养生态位分化,种间竞争不激烈。综上所述,从目前三峡库区现有短颌鲚营养生态位特征来看,其种群规模仍有进一步扩大的可能。上述研究结果可为全面了解三峡库区外来鱼类的适应对策提供研究思路和基础数据。     

中国跳鼠总科物种的系统分类学研究进展

近年来,随着分子系统学的发展以及荒漠地区物种多样性和分类学研究的深入,新的隐存种不断被发现,一些类群的分类地位也发生了变动。中国是世界上跳鼠总科（Dipodoidea）物种多样性最高的国家,通过对中国跳鼠总科物种的分类系统进行重新梳理和研究,确认跳鼠总科在中国有3科6亚科12属22种。证实中国分布有第五种蹶鼠——灰蹶鼠（Sicista pseudonapaea）。五趾跳鼠亚科原属Allactaga是一个并系群,应拆分为Allactaga、Orientallactaga、Scarturus三个属;原五趾跳鼠、巨泡五趾跳鼠、巴里坤跳鼠归于Orientallactaga属,小五趾跳鼠移入Scarturus属,且是一个包含隐存种的种团。大五趾跳鼠在我国仅有文献记载,其分布存疑。跳鼠亚科原三趾跳鼠努日亚种提升为种——塔里木跳鼠（Dipus deasyi）;而准噶尔羽尾跳鼠（Stylodipus sungorus）在我国有分布。奇美跳鼠（Chimaerodipus auritus）是近年来在我国发现并命名的新属新种。     

浑善达克沙地三趾跳鼠体重与年龄划分

哺乳动物的年龄划分始终是动物种群生态学研究的基础内容之一,同时鼠类年龄划分方法在害鼠的预测和控制实践中具有十分重要的意义。国内外对于三趾跳鼠的生态、疫病、进化等方面进行过一些研究,但有关该鼠种年龄鉴定的研究和鼠类年龄组划分与鼠种的实际年龄对应的研究尚属空白。2002年到2003年间,我们在内蒙古锡林郭勒盟浑善达克沙地,采用常规夹线方法对三趾跳鼠(Dipus sagitta)的种群年龄进行调查,对每只捕获的三趾跳鼠样本进行了体长、体重、胴体重、繁殖特征进行记录,利用胴体重为标准,参考样本出现的时间（月份）及繁殖特征,将三趾跳鼠划分年龄组。结果表明,捕获到的三趾跳鼠可划分为3个自然年龄组,1龄组（胴体重≤71 g）,2龄组（71<胴体重≤90 g）,3龄组及以上（胴体重>90 g）,三趾跳鼠最大年龄至少3龄。鉴定三趾跳鼠年龄运用胴体重法相对简便准确。     

应用脂肪酸组成研究热带东太平洋同域中上层鲨鱼营养生态位分化

物种对食物资源利用方式的差异,即营养生态位分化是物种共存的先决条件之一,对种间营养生态位的比较研究有助于了解同域分布物种的共存机制。脂肪酸组成可反映生物较长时间尺度的摄食信息,对探讨物种间营养生态位分化具有重要指示作用。热带东太平洋主要栖息有8种大型中上层鲨鱼,大青鲨(Prionace glauca)、大眼长尾鲨(Alopias superciliosus)、镰状真鲨(Carcharhinus falciformis)、长鳍真鲨(Carcharhinus longimanus)、浅海长尾鲨(Alopias pelagicus)、尖吻鲭鲨(Isurus oxyrinchus)、路氏双髻鲨(Sphyrna lewini)和锤头双髻鲨(Sphyrna zygaena),通过比较其肌肉脂肪酸组成,分析种间食性差异,营养关系及营养生态位分化。结果表明,尖吻鲭鲨营养级相对较高,大青鲨相对较低。3种鼠鲨与5种真鲨存在食性差异或栖息地隔离。浅海长尾鲨与大眼长尾鲨营养生态位重叠程度较高,存在激烈的资源竞争。大青鲨与镰状真鲨生态位宽度较大,表征其对环境的可塑性较强;尖吻鲭鲨和路氏双髻鲨生态位宽度较小,表现为其食性的特化。本研究解释了脂肪酸组成分析在鲨鱼摄食研究中的潜在应用,对分析大洋性鲨鱼的营养生态位分化,资源分配方式及同域共存机制有一定的应用价值。     

黄河口近海海草床浮游-底栖营养传递特征

为了探寻海草床浮游-底栖营养传递耦合特征,于2017年7月对黄河口近海海草床碳源和消费者功能群进行样品采集和碳氮稳定同位素（δ¹³C和δ¹⁵N）测定,计算了消费者功能群的营养级,利用基于贝叶斯的稳定同位素混合模型定量化消费者功能群的食源组成,计算了消费者功能群的浮游、底栖营养贡献比例。结果表明：黄河口近海海草床的碳源和消费者功能群的δ¹³C和δ¹⁵N值均呈现显著性差异（P<0.05）,浮游碳源的δ¹³C值显著低于底栖碳源,消费者功能群的营养级范围为1.49-4.20。浮游动物和腹足类分别由浮游和底栖营养传递途径提供能量来源,其余消费者功能群共同依赖于这两种营养传递路径。消费者功能群随着浮游营养贡献比例的增加,其δ¹³C值逐渐降低。反之,随着底栖营养贡献比例的增加,其δ¹³C值逐渐增加。这与浮游碳源和底栖碳源的δ¹³C值的分化现象一致。对该海草床营养传递特征的系统性定量化解析有助于了解海草床的能量传递模式,为海草床的生态保护和修复提供系统性视角。     

几种跳鼠自然繁殖情况的初步观察

1985年1—12月在灵武县临河地区共捕羽尾跳鼠184只、五趾跳鼠169只、三趾跳鼠136只。雌雄性比,羽尾跳鼠为1∶0.8,五趾跳鼠为1∶2.31,三趾跳鼠为1∶0.9。羽尾跳鼠雌鼠4—9月均可繁殖。五趾跳鼠雌鼠4—8月为繁殖期。三趾跳鼠雌鼠4—9月为繁殖期。几种雄性鼠中,羽尾跳鼠一出蛰就有很强的繁殖能力,6月份达到高峰。五趾跳鼠4月初出蛰就有较强的繁殖能力,5、6月达到高峰。三趾跳鼠4、5月的繁殖能力较强,6、7月达到高峰。     

用水晶体干重鉴定五趾跳鼠的种年龄

利用556只五趾跳鼠的水晶体干重作次数分配,将该鼠年龄划分成7个组进行观察：幼年组水晶体干重在55.00毫克以下,亚成年组55.01-77.50毫克（当年出生）,成年Ⅰ组55.01-87.50毫克（经过一次冬眠并参加繁殖）,成年Ⅱ组87.51-102.50毫克,成年Ⅲ组102.51-117.50毫克,成年Ⅳ组117.51-130.00毫克,老年组130.01毫克以上。据1986和1987年的观察,结果表明五趾跳鼠年龄组成季节变化明显,年度之间没有显著变化。     

围封和放牧对科尔沁沙地植物群落种间关联的影响

为明确围封和放牧对科尔沁沙地植物群落种间关联的影响,在对植物群落进行样方调查的基础上,采用方差比率法（VR）、χ²检验、Ochiai指数、Spearman秩相关分析对种间关联性及相关性进行研究,得出如下结论：（1）围封和放牧改变了群落物种组成,围封群落出现30个物种,主要物种16个;放牧群落出现物种21个,主要物种13个。（2）VR值显示围封和放牧群落总体均呈正关联性,χ²检验表明围封群落正联结显著率大于负联结显著率,主要物种间显著联结率为27.5%,放牧群落仅有显著正联结种对4个,占6.06%,OI值与χ²检验结果基本一致。（3） Spearman秩相关分析表明,围封群落显著正相关对数略高于显著负相关对数,放牧群落则相反,且围封群落显著相关水平种对占比（44.17%）高于放牧群落（12.82%）,故围封群落处于稳定发展阶段,而放牧群落处于退化阶段。     

Foreign exploration for Scirtothrips perseae Nakahara (Thysanoptera: Thripidae) and associated natural enemies on avocado (Persea americana Miller)

Scirtothrips perseae Nakahara was discovered attacking avocados in California, USA, in 1996. Host plant surveys in California indicated that S. perseae has a highly restricted host range with larvae being found only on avocados, while adults were collected from 11 different plant species. As part of a management program for this pest, a “classical” biological control program was initiated and foreign exploration was conducted to delineate the home range of S. perseae, to survey for associated natural enemies and inventory other species of phytophagous thrips on avocados grown in Mexico, Guatemala, Costa Rica, the Dominican Republic, Trinidad, and Brazil. Foreign exploration efforts indicate that S. perseae occurs on avocados grown at high altitudes (>1500 m) from Uruapan in Mexico south to areas around Guatemala City in Guatemala. In Costa Rica, S. perseae is replaced by an undescribed congener as the dominant phytophagous thrips on avocados grown at high altitudes (>1300 m). No species of Scirtothrips were found on avocados in the Dominican Republic, Trinidad, or Brazil. In total, 2136 phytophagous thrips were collected and identified, representing over 47 identified species from at least 19 genera. The significance of these species records is discussed. Of collected material 4% were potential thrips biological control agents. Natural enemies were dominated by six genera of predatory thrips (Aeolothrips, Aleurodothrips, Franklinothrips, Leptothrips, Scolothrips, and Karnyothrips). One genus each of parasitoid (Ceranisus) and predatory mite (Balaustium) were found. Based on the results of our sampling techniques, prospects for the importation of thrips natural enemies for use in a “classical” biological control program in California against S. perseae are not promising.     

Phylogeny of cardinalfishes (Teleostei: Gobiiformes: Apogonidae) and the evolution of visceral bioluminescence

The cardinalfishes (Apogonidae) are a diverse clade of small, mostly reef-dwelling fishes, for which a variety of morphological data have not yielded a consistent phylogeny. We use DNA sequence to hypothesize phylogenetic relationships within Apogonidae and among apogonids and other acanthomorph families, to examine patterns of evolution including the distribution of a visceral bioluminescence system. In conformance with previous studies, Apogonidae is placed in a clade with Pempheridae, Kurtidae, Leiognathidae, and Gobioidei. The apogonid genus Pseudamia is recovered outside the remainder of the family, not as sister to the superficially similar genus Gymnapogon. Species sampled from the Caribbean and Western Atlantic (Phaeoptyx, Astrapogon, and some Apogon species) form a clade, as do the larger-bodied Glossamia and Cheilodipterus. Incidence of visceral bioluminescence is found scattered throughout the phylogeny, independently for each group in which it is present. Examination of the fine structure of the visceral bioluminescence system through histology shows that light organs exhibit a range of morphologies, with some composed of complex masses of tubules (Siphamia, Pempheris, Parapriacanthus) and others lacking tubules but containing chambers formed by folds of the visceral epithelium (Acropoma, Archamia, Jaydia, and Rhabdamia). Light organs in Siphamia, Acropoma, Pempheris and Parapriacanthus are distinct from but connected to the gut; those in Archamia, Jaydia, and Rhabdamia are simply portions of the intestinal tract, and are little differentiated from the surrounding tissues. The presence or absence of symbiotic luminescent bacteria does not correlate with light organ structure; the tubular light organs of Siphamia and chambered tubes of Acropoma house bacteria, those in Pempheridae and the other Apogonidae do not.     

Molecular phylogeny of Phebalium (Rutaceae: Boronieae) and related genera based on the nrDNA regions ITS 1+2

Parsimony analyses of the internal transcribed spacer regions of nuclear ribosomal DNA (ITS 1 & ITS 2) for 38 taxa sampled from the Phebalium group (Rutaceae: Boronieae) and two outgroups confirm that, with the exception of Phebalium sensu stricto and Rhadinothamnus, six of the currently recognised genera within the group are monophyletic. The data indicate that Phebaliums. str. is paraphyletic with respect to Microcybe, and Rhadinothamnus is paraphyletic with respect to Chorilaena. Rhadinothamnus and Chorilaena together are the sister group to Nematolepis. Drummondita, included as an outgroup taxon, clustered within the ingroup as sister to Muiriantha and related to Asterolasia.The phylogeny suggests that the evolution of major clades within a number of these genera (e.g. Phebalium) relates to vicariance events between eastern and south-western Australia. Leionema is an eastern genus, with the most basal taxon being the morphologically distinct Leionema ellipticum from northern Queensland. Leionema also includes one species from New Zealand, but this species (as with some others) proved difficult to sequence and its phylogenetic position remains unknown. Taxonomic changes at the generic level are recommended.The authors wish to thank Paul G.Wilson, PERTH, for advice and discussion, and Paul Forster, BRI, for collecting and providing material of Leionema ellipticum. The project was supported by a Melbourne University Postgraduate Award (to BM), the Australian Biological Resources Study (ABRS), Australian Systematic Botany Society and Wolf Den (Australia) Investments.     

Tracking down the "head blob": comparative analysis of wingless expression in the developing insect procephalon reveals progressive reduction of embryonic visual system patterning in higher insects

The evolution of larval head morphology in holometabolous insects is characterized by reduction of antennal appendages and the visual system components. Little insight has been gained into molecular developmental changes underlying this morphological diversification. Here we compare the expression of the segment polarity gene wingless (wg) in the pregnathal head of fruit fly, flour beetle and grasshopper embryos. We provide evidence that wg activity contributes to segment border formation, and, subsequently, the separation of the visual system and protocerebrum anlagen in the anterior procephalon. In directly developing insects like grasshopper, seven expression domains are formed during this process. The activation of four of these, which correspond to polar expression pairs in the optic lobe anlagen and the protocerebral ectoderm, has shifted to postembryonic stages in flour beetle and Drosophila. The remaining three domains map to the protocerebral neuroectoderm, and form by disintegration of a large precursor domain in flour beetle and grasshopper. In Drosophila, the precursor domain remains intact, constituting the previously described “head blob”. These data document major changes in the expression of an early patterning gene correlated with the dramatic evolution of embryonic visual system development in the Holometabola.     

Molecular identification of Taenia spp. in wolves (Canis lupus), brown bears (Ursus arctos) and cervids from North Europe and Alaska

Taenia tapeworms of Finnish and Swedish wolves (Canis lupus) and Finnish brown bears (Ursus arctos), and muscle cysticerci of Svalbard reindeer (Rangifer tarandus platyrhynchus), Alaskan Grant's caribou (Rangifer tarandus granti) and Alaskan moose (Alces americanus) were identified on the basis of the nucleotide sequence of a 396 bp region of the mitochondrial cytochrome c oxidase subunit 1 gene. Two species were found from wolves: Taenia hydatigena and Taenia krabbei. The cysticerci of reindeer, caribou and one moose also represented T. krabbei. Most of the cysticercal specimens from Alaskan moose, however, belonged to an unknown T. krabbei-like species, which had been reported previously from Eurasian elks (Alces alces) from Finland. Strobilate stages from two bears belonged to this species as well. The present results suggest that this novel Taenia sp. has a Holarctic distribution and uses Alces spp. as intermediate and ursids as final hosts.     

中国石蕊科地衣研究之四石蕊属地衣新种及中国新记录

摘要:本文报道了中国横断山地区石蕊属地衣12种,其中新种1个:贡嘎石蕊(Cladonia ngganensis S.Y. Guo & Wei),中国新记录11种:类黄粉石蕊(Cl. bacilliformis),比蒙氏石(Cl. beaumontii),小棍棒石蕊(Cl. clavulifera),圆筒石蕊(Cl. cylindrica),具粉石蕊(Cl. farinacea),北海道石蕊(Cl. hokkaidensis),厚叶石蕊(Cl. incrassata),大叶石蕊(Cl. macrophylla),丛杯石蕊( Cl. mateocyatha),多孔石蕊(Cl. multiformis)和亚石蕊(Cl. subrangiformis)。对于每一种的化学成分及地理分布进行了测定和分析。     

Fungal Thyroiditis: An Overview

The authors review the epidemiology, clinical manifestations, diagnosis, and treatment of fungal thyroiditis cases previously reported in the medical literature. Aspergillus was by far the most common cause of fungal thyroiditis. Immunocompromised patients, such as those with leukemia, lymphoma, autoimmune diseases, and organ-transplant patients on pharmacological immunosuppression were particularly at risk. Fungal thyroiditis was diagnosed at autopsy as part of disseminated infection in a substantial number of patients without clinical manifestations and laboratory evidence of thyroid dysfunction. Local signs and symptoms of infection were indistinguishable from other infectious thyroiditis and included fever, anterior cervical pain, thyroid enlargement sometimes associated with dysphagia and dysphonia, and clinical and laboratory features of transient hyperthyroidism due to the release of thyroid hormone from follicular cell damage, followed by residual hypothyroidism. Antemortem diagnosis of fungal thyroiditis was made by direct microscopy and culture of a fine-needle aspirate, or/and biopsy in most cases. Since most patients with fungal thyroiditis had disseminated fungal infection with delay in diagnosis and treatment, the overall mortality was high.     

安徽牯牛降的丝孢菌Ⅰ

本文报导作者采自安徽枯牛降自然保护区的18种丝孢菌,分属于5个属,其中有3个新种:牛皮冻生尾孢(Cercospora paederiicola),山鸡椒假尾饱(Pseudocercospora litseae-cubebae),鸡血藤生假尾孢(P. millettiicola)和2个中国新纪录。文中对新种进行了描述及绘图,新记录种作了简要说明。研究的标本保存在中国科学院微生物研究所真菌标本室(HMAS)。     

Changes of dung beetle communities from rainforests towards agroforestry systems and annual cultures in Sulawesi (Indonesia)

Little is known about how tropical land-use systems contribute to the conservation of functionally important insect groups, including dung beetles. In a study at the margin of Lore Lindu National Park (a biodiversity hotspot in Central Sulawesi, Indonesia) dung-beetle communities were sampled in natural forest, young secondary forest, agroforestry systems (cacao plantations with shade trees) and annual cultures (maize fields), each with four replicates (n = 16 sites). At each site we used 10 pitfall traps, baited with cattle dung, along a 100 m transect for six 3-day periods. The number of trapped specimens and species richness at the natural forest sites was higher than in all land-use systems, which did not significantly differ. Each land-use system contained, on average, 75% of the species richness of the natural forest, thereby indicating their importance for conservation. However, a two-dimensional scaling plot based on NESS indices (m = 6) indicated distinct dung beetle communities for both forest types, while agroforestry systems and annual cultures exhibited a pronounced overlap. Mean body size of dung beetles was not significantly influenced by land-use intensity. Five of the six most abundant dung beetle species were recorded in all habitats, whereas the abundance of five other species was significantly related to habitat type. Mean local abundance and number of occupied sites were closely correlated, further indicating little habitat specialisation. The low dung beetle diversity (total of 18 recorded species) may be due to the absence of larger mammals in Sulawesi during historical times, even though Sulawesi is the largest island of Wallacea. In conclusion, the dung beetle fauna of the lower montane forest zone in Central Sulawesi appears to be relatively robust to man-made habitat changes and the majority of species did not exhibit strong habitat preferences.