湖北五峰后河国家级自然保护区鸟类多样性

为了解湖北五峰后河国家级自然保护区(以下简称后河保护区)鸟类物种多样性及其区系组成的变化, 我们通过样线、红外相机调查和检索文献资料相结合的方法获得了后河保护区鸟类名录, 并将其与后河保护区1999年科学考察结果进行对比分析。本研究于2017-2019年共在后河保护区内设置了82 km的鸟类调查样线, 共在309个位点上放置了红外相机, 累计99,586个相机日。我们用“后河” “鸟类” “湖北省”等关键词搜索相关出版物, 并查阅中国观鸟记录中心经审核后发布的鸟类信息, 结合样线和红外相机调查结果形成后河保护区鸟类名录。共整理得到后河保护区鸟类255种, 隶属于16目55科。其中, 国家I级重点保护野生鸟类2种, 包括中华秋沙鸭(Mergus squamatus)和金雕(Aquila chrysaetos); 国家II级重点保护野生鸟类46种, 包括红腹角雉(Tragopan temminckii)、棉凫(Nettapus coromandelianus)、松雀鹰(Accipiter virgatus)、灰林鸮(Strix aluco)、蓝鹀(Emberiza siemsseni)等。此外, 后河保护区有11种中国特有鸟类, 占我国特有鸟类种数(n = 93)的11.83%。在区系成分上, 后河保护区鸟类以东洋种为主(151种, 占59.22%), 其次为广布种(55种, 占21.57%)。与1999年科学考察结果相比, 鸟类增加了116种, 其中有15种国家重点保护野生鸟类。在区系组成上, 后河保护区内东洋种占比增加, 包括分布区向北扩散的物种成分。此外, 本次调查未记录到20世纪在保护区内有分布的白冠长尾雉(Syrmaticus reevesii)和海南鳽(Gorsachius magnificus)。本研究表明, 后河保护区鸟类物种多样性高、特有种及珍稀濒危物种丰富, 具有极高的保护价值和意义。通过对比分析后河保护区内野生鸟类动态变化, 可为保护区生物多样性监测方案设计和保护对策的制定提供科学依据。     

高原鼠兔干扰对高寒草甸β多样性的影响

β多样性反映生物群落沿某一环境梯度的物种周转速率, 该研究尝试采用β多样性揭示植物群落随小型啮齿草食动物干扰梯度变化的生态过程。该研究利用野外随机样地的采集数据, 分析了高原鼠兔(Ochotona curzoniae)不同干扰强度下Whittaker指数的变化特征, 并利用群落二元丰富度的方差分解法, 确定了单个物种(SCBD)和单个干扰位点(LCBD)对β多样性的贡献。主要结果: 随高原鼠兔干扰强度增加, 植物群落内物种周转速率呈先增加后降低的趋势; 占据位点数居中的物种对区域内的β多样性贡献较大, 其中冰草(Agropyron cristatum)、臭蒿(Artemisia hedinii)、小花草玉梅(Anemone rivularis var. flore-minore)等单个物种对整个区域内β多样性的贡献最为突出; 整个区域内干扰位点T₀ (高原鼠兔干扰强度为0)对区域β多样性贡献值最大, LCBD值和该位点的群落丰富度呈显著负相关关系, 但与高原鼠兔干扰强度无显著关联。说明重点保护LCBD值高的干扰位点所在的高寒草甸, 以及SCBD值较高的冰草、臭蒿、小花草玉梅, 对保护高原鼠兔存在时高寒草甸植物群落多样性具有重要意义。     

Chemotaxonomy of Gentianopsis: Xanthones, C-glycosylflavonoids and carbohydrates

In the genus Gentiana s.l. (Gentianaceae), the status of the section Crossopetalum Froel, is still very much debated. On Morphological grounds. Ma regarded this section as an independent genus which he called Gentianopsis. In this paper we discuss this proposal, taking into account chemotaxonomic data (xanthones, carbohydrates and C-glycosylflavones) arising from an examination of leaves and flowers of 13 species including the type-species Gentianopsis barbata. Isoscoparin, primeverose. 1,3,7- and 1,3,7,8-O-substituted xanthones were present in all species, while 1,3,5,8-O-substituted xanthones were absent. These criteria clearly differentiate the group from Gentianella (occurrence of 1,3,5,8-O-substituted xanthones, absence of 1,3,7-O-substituted xanthones, presence of swertisin, absence of primeverosel in which they were previously included. Furthermore, a comparison of Crossopetalum with two species belonging to Gentiana s.s. (the type G. lutea L. and G. orbicularis Schur.) discloses some analogy with respect to xanthone composition (only 1,3,7- or 1,3,7,8-substitution, respectively). However, the presence of gentianoise in Gentiana s.s., in contrast to its absence in Gentianopsis, indicates that the latter should be excluded from Gentiana. The assessment on morphological grounds of the validity of the genus Gentianopsis Ma is thus reinforced. The evolutionary signification of the chemical characters and the phyletic relationships of Gentianopsis with the other genera of the Gentianinae are discussed.     

滇西南四个自然保护区鱼类多样性及评价指标探究

为了解滇西南怒江水系的南滚河自然保护区、南捧河自然保护区、永德大雪山自然保护区及澜沧江水系的澜沧江自然保护区鱼类多样性和变化趋势, 探讨其差异和变化的原因, 本文采用β多样性指数分析了4个保护区的鱼类多样性, 并比较了鱼类分类阶元的特有性、单型性和古老成分的有无等多项指标。结果显示, 4个自然保护区共有土著鱼类85种, 隶属于6目13科45属。在中国仅见于怒江水系的4个特有属有异鲴属(Aspidoparia)和新条鳅属(Neonoemacheilus)分布于这3个保护区中; 18种特有种中, 仅分布在这3个保护区的狭域特有种5种。在中国仅分布于澜沧江水系的属有31个, 但仅安巴沙鳅属(Ambastaia)分布于澜沧江保护区; 在澜沧江保护区分布着中国仅见于澜沧江水系的特有种20种, 其中狭域特有种3种。怒江水系的3个保护区分布有1个单型属, 即鳗鲡属(Anguilla), 但没有单型种; 澜沧江自然保护区无单型属与单型种分布。4个保护区中的鱼类均系晚第三纪和第四纪形成的种类或类群, 没有古老或孑遗种类。β多样性结果显示, 在4个保护区中澜沧江自然保护区的鱼类多样性最丰富, 而南滚河自然保护区的丰富程度最低, 但是怒江水系3个自然保护区鱼类多样性的代表性及保护地位比澜沧江自然保护区的要高。而特有阶元和单型性阶元的存在体现出怒江水系3个自然保护区的保护价值及保护意义比澜沧江保护区高。地理范围跨度大小、生境空间异质性高低、保护区面积大小及支流多少等是影响鱼类多样性的主要因素。因此, 规划和设计保护区时, 如果能在水系的上、中、下游分别规划1条一级支流作为保护区, 可使该水系的绝大多数鱼类得到保护。     

鹅膏环肽毒素生源合成的研究进展

在蘑菇目Agaricales中,已知鹅膏属Amanita、环柄菇属Lepiota和盔孢伞属Galerina 3个属的部分物种能产生剧毒的鹅膏环肽毒素。全球90%以上的致死性蘑菇中毒事件是由含鹅膏环肽蘑菇导致。上述3个属的剧毒蘑菇虽然亲缘关系较远,但却可以合成同一种鹅膏环肽毒素,且使用了大致相同的生源合成代谢途径,涉及多个毒素合成基因,采用了特殊的组合式合成机制。本文总结了鹅膏环肽毒素合成途径研究的最新进展,指出了当前工作中遇到的一些难题,对未来研究的趋势进行了展望。     

中国拟家鼠分类与分布厘订

拟家鼠(Rattus pyctoris)由Hodgson在1845年命名,其模式产地为尼泊尔。该种的分类地位和是否在中国有分布都存在较大争议。近来有研究认为拟家鼠不分布于我国。2020年,在西藏吉隆县和札达县进行野外调查时采集到7号标本,皮毛、头骨和牙齿的形态特征与尼泊尔的拟家鼠相似,分子系统发育分析支持这些标本为单系(PP=1.0),与模式产地样品C_yt b基因的K2?P遗传距离为0~2.8%,确认这些标本为拟家鼠。这是第一次在我国境内采集到拟家鼠标本,丰富和完善了这个物种的生物地理资料。     

Glaucolides from old world Vernonia species

The investigation of two East African and a Madagascarian Vernonia species afforded several new sesquiterpene lactones. Vernonia colorata subsp. grandis gave 19-hydroxyglaucolide A and three vernodalin derivatives, V. holstii five new cistifoliolides and V. zanzibarensis five lactones closely related to brachycalyxolide. The structures were elucidated by high field NMR techniques. The chemotaxonomic relevance is discussed briefly.     

Experiments on the physiology of southern and northern krill, Euphausia superba and Meganyctiphanes norvegica, with emphasis on moult and growth - a review

Physiological data are needed for life history studies on krill, and as parameters for input into energy budgets and models. In conjunction with moult and growth data, these may also prove useful for assessing the fishable biomass of krill. Here, the development of physiological concepts in experimental krill research is briefly evaluated, with emphasis on the gaps to be filled. Krill growth is very flexible, as well as strongly temperature and nutrition dependent. The polar Antarctic krill Euphausia superba grows as fast as the boreal species Meganyctiphanes norvegica, at least during the first 2.5 years, and the species are comparable in terms of physiological plasticity. Accordingly, as krill appear to adjust quickly to specific laboratory conditions, short-term experiments are essential if field conditions are to be reflected as closely as possible. Furthermore, direct comparisons between laboratory experiments and swarming studies in the field are advantageous. For these, M. norvegica is particularly well-suited, as swarms can be followed over longer times and more easily than in E. superba. For example, processes of moult and reproduction were found to be highly coordinated in swarms and populations of Northern krill. For this species a conceptual model of reproduction was developed based on a combination of short-term laboratory observations coupled with field data on moult and ovary stages. In further physiological experiments krill should be studied as groups when swarming. Using proxies, that is applying physiological and/or biochemical methods side by side, is a promising way to enhance the reliability of life history data.     

Biochemical systematics of Allodontichthys: A genus of goodeid fishes

Allodontichthys Hubbs and Turner 1939 of the family Goodeidae is comprised of three species: A. tamazulae and A. hubbsi from the Rio Coahuayana and A. zonistius from the Rio Armeria in Estados Jalisco and Colima, Mexico. These fish are found throughout the shallow riffles of small streams. Their systematics has been based on morphological and karyological traits. An alloenzymic study of the genus produced results which agree well with the previous morphological studies. Moreover, a dendrogram of Nei genetic identities agrees well with the zoogeography of the species. The data indicate a high degree of congruence between alloenzymic and morphological systematic inferences in this group of fishes.     

弄岗北热带喀斯特季节性雨林15 ha监测样地的树种组成与空间分布

北热带喀斯特季节性雨林(northern tropical karst seasonal rain forest)是在我国热带北缘喀斯特地区分布的典型森林植被类型之一。由于富钙偏碱的地球化学背景及多样性的生境类型, 同时受季风气候影响, 该森林呈现群落结构多样、树种组成丰富、特有成分突出等特点。基于大型固定监测样地对该森林树种组成与空间分布进行的研究, 是探明该区域生物多样性形成与维持机制的基础。我们于2011年底建立了广西弄岗北热带喀斯特季节性雨林15 ha监测样地, 依照CTFS (Center for Tropical Forest Science)全球森林生物多样性监测规范, 定位并调查了样地内每一棵胸径≥1 cm的木本植物。结果表明: (1)样地内有监测树种223种, 隶属于56科157属; 独立个体总数为68,010株(含分枝为95,471株), 平均胸径为4.84 cm; (2)树种科、属的区系均以热带成分为主, 大戟科、马鞭草科、梧桐科等为优势科; (3)个体数最多的11个树种的个体数之和占到总个体数的51.64%, 前58个树种的占90.19%; 稀有种有75种, 占总树种数的33.63%; (4)群落结构稳定且更新良好, 主要优势种的径级结构均呈倒“J”形, 无明显断层; (5)树种分布在空间上表现出明显差异, 黄梨木(Boniodendron minus)等强耐旱型树种分布于山顶周围; 蚬木(Excentrodendron tonkinense)等树种分布于山坡中部; 对叶榕(Ficus hispida)等喜湿耐荫型树种分布于山谷周围; (6)胸径>20 cm的个体较多分布在山坡中下部, 极少分布在山顶周围; 胸径10–20 cm的个体较均匀分布于整个样地; 分枝和萌枝较多分布在山顶周围; (7)种–面积散点图在2–7 ha的取样面积下分化形成两条曲线, 表明了树种数量组成在空间上具有强烈异质性。研究初步认为: 强烈生境异质性及独特地质背景可能是影响该喀斯特森林物种组成及空间分布的重要因素。     

Comparison of the feeding habits of Eurasian otters on a fast flowing river and its backwater habitats

The diet and feeding habits of Eurasian otters Lutra lutra were studied by spraint analysis over a 2- year period, on three sections of the Drava River and three backwaters, in south-west Hungary. The primary food was fish (mean: 89.8% and 87.5% for riverine and backwater habitats, respectively); otters living in riverine habitats compared to backwaters, consumed more birds (3.9% and 0.7%, respectively), less mammals (0.5% and 0.9%, respectively), less reptiles and amphibians (5.6% and 10.2%, respectively) and less invertebrates (0.1% and 0.6%, respectively). In riverine habitats otters preyed more frequently on larger fish than in backwaters, but the main fish prey was small-sized (below 100 g in weight, 85.6% and 91.7%, respectively). On river sections they preyed more frequently on reophil (flow preferring fish, 18.9% and 3.3%, respectively), and less on stagnophil fish (stagnant waters preferring, 9.8% and 24.5%, respectively) than in backwaters. The main fish prey was eurytopic (tolerant of rivers and stagnant waters, 71.3% and 72.2%, respectively). Preference (by Ivlev's electivity index, E_i) in the Drava River for various fish guilds differed, as the otters preferred eurytopic (E_i= 0.30) and stagnophil fish (E_i= 0.24), and avoided reophil fish (E_i=−0.58). Otters did not threaten the rare, flow preferring fish species and the main diet consisted of economically unimportant species.     

Some ecological aspects of the copepod parasites of the common hake, Merluccius hubbsi, from the Argentine-Uruguayan coasts

A total of 2164 common hake Merluccius hubbsi captured in the Argentine-Uruguayan Common Fishing Zone was examined for parasitic copepods. The fish were infested with Chondracanlhus palpifer and Neobrachietia insidiosa f. lageniformis, the former parasitizing the buccal cavity and the latter the branchial arches. C. palpifer showed an increase in both prevalence and intensity in relation to the host size; infestation with N. insidiosa f. lageniformis decreased with increasing length of hake. Attachment site preferences and variations in the parasite distribution patterns as related to the host biology were observed. Evidence of negative association between copepod species and seasonal changes in the parasite composition was also found.     

The Primulales: Serological contributions to the problem of their systematic position

The distribution of serological determinants in seed proteins from different species of Primulaceae, as well as from Ardisia crenulata (Myrsinaceae), Erica tetralix (Ericaceae), Manilkara zapota (Sapotaceae, Ebenales). Actinidia chinensis (Actinidiaceae) and Armeria maritima (Plumbaginaceae) has been determined by the use of corresponding rabbit immune sera. Serological reactions were carried out using a gel diffusion micro-method in calcium alginate gel, and a special pre-absorption technique was used in order to more closely specify the distribution of serological characteristics in the taxa under examination. While no systematic similarities were found between Primulales and Plumbaginales, a serological correspondence between Primulales and Ericales is very clear. It also occurs between these two taxa and species of the Theales. The Sapotaceae (as representatives of the Ebenales) showed some serological similarities with the Theales.     

Polyhydroxyalkaloids in the Aroid Tribes Nephthytideae and Aglaonemateae: Phytochemical Support for an Intertribal relationship

Using living and herbarium material, a survey of polyhydroxyalkaloids in species of 52 genera of Araceae revealed the presence of 2,5-dihydroxymethyl-3,4-dihydroxypyrrolidine (DMDP) and -homonojirimycin (HNJ) in leaves of Nephthytis Schott, Anchomanes Schott, Pseudohydrosme Engl. (tribe Nephthytideae), Aglaonema Schott and Aglaodorum Engl. (tribe Aglaonemateae). Levels were high in living plants, ranging from 0.1 to 1% dry weight DMDP and 0.04 to 0.6% HNJ. Isomers of HNJ, such as -3,4-di-epi-homonojirimycin, were also present in the five genera. Seven of the eight Nephthytis species examined also contained deoxymannojirimycin at levels, in fresh material, of 0.1–0.2% dry weight. Lower levels of DMDP (mean 0.009%) and HNJ (mean 0.002%) were detected in species of Amorphophallus Blume & Decne and Pseudodracontium N.E. Br. (tribe Thomsonieae). The similarity in polyhydroxyalkaloid chemistry between Nephthytideae and Aglaonemateae concurs with recently published chloroplast restriction site data in suggesting a relationship between these tribes.     

Clerodane diterpenoids from the roots of Portulaca pilosa

Three trans-clerodane diterpenoids, pilosanol A, B and C, the last compound being a glucoside, have been isolated from the roots of Portulaca pilosa. They show a marked contrast in skeletal type with the constituents of aerial part. Evolutionary changes in the biosynthetic abilities of Portulaca species is discussed.     

Composition of the photosystems and chloroplast structure in extreme shade plants

Chloroplasts were isolated from leaves of three species of tropical rainforest plants, Alocasia macrorrhiza, Cordyline rubra and Lomandra longifolia; these species are representative of extreme “shade” plants. It was found that shade plant chloroplasts contained 4–5 times more chlorophyll than spinach chloroplasts. Their chlorophyll a/chlorophyll b ratio was 2.3 compared with 2.8 for spinach. Electron micrographs of leaf sections showed that the shade plant chloroplasts contained very large grana stacks. The total length of partitions relative to the total length of stroma lamellae was much higher in Alocasia than in spinach chloroplasts. Freeze-etching of isolated chloroplasts revealed both the small and large particles found in spinach chloroplasts.

Despite their increased chlorophyll content, low chlorophyll a/chlorophyll b ratio, and large grana, the shade plant chloroplasts were fragmented with digitonin to yield small fragments (D-144) highly enriched in Photosystem I, and large fragments (D-10) enriched in Photosystem II. The degree of fragmentation of the shade plant chloroplasts was remarkably similar to that of spinach chloroplasts, except that the subchloroplast fragments from the shade plants had lower chlorophyll a/chlorophyll b ratios than the corresponding fragments from spinach. The D-10 fragments from the shade plants had chlorophyll a/chlorophyll b ratios of 1.78-2.00 and the D-144 fragments ratios of 3.54–4.07. We conclude that Photosystems I and II of the shade plants have lower proportions of chlorophyll a to chlorophyll b than the corresponding photosystems of spinach. The lower chlorophyll a/chlorophyll b ratio of shade plant chloroplasts is not due to a significant increase in the ratio of Photosystem II to Photosystem I in these chloroplasts.

The extent of grana formation in higher plant chloroplasts appears to be related to the total chlorophyll content of the chloroplast. Grana formation may simply be an means of achieving a higher density of light-harvesting assemblies and hence a more efficient collection of light quanta.     

灌丛移除对荒漠齿肋赤藓越冬过程中生理生化特性的影响

灌丛和生物土壤结皮镶嵌分布是古尔班通古特沙漠一种重要的地表覆被类型, 灌丛的存在不仅为小型动物提供了庇护场所, 也为隐花植物及部分草本植物创造了良好的生存条件。然而在初冬时期移除灌丛是否会影响这些隐花植物的越冬及生长还不得而知。该研究通过模拟放牧及鼠害, 移除50%双穗麻黄(Ephedra distachya)灌丛、移除全部双穗麻黄灌丛及自然对照, 测定齿肋赤藓(Syntrichia caninervis)植株脯氨酸、可溶性糖和可溶性蛋白含量, 以及丙二醛(MDA)含量和超氧化物歧化酶(SOD)、过氧化物酶(POD)和过氧化氢酶(CAT) 3种抗氧化酶活性, 并测定原位光化学效率, 探讨初冬灌丛丧失对荒漠藓类植物越冬的影响。结果表明, 在积雪期3种处理下齿肋赤藓的游离脯氨酸和可溶性糖含量之间差异并不显著, 但去灌丛后其MDA含量、POD、SOD和CAT 3种抗氧化酶活性均显著高于自然灌丛下齿肋赤藓的相关生理指标。即使是在融雪期, 去灌丛下齿肋赤藓的可溶性糖含量及POD和CAT活性仍显著高于自然灌丛, 而可溶性蛋白明显较低, 这可能是由于灌丛的丧失造成的温度波动加剧了冬季低温对藓类植物的伤害。灌丛的部分移除(50%)对齿肋赤藓的生理生化特性影响不显著, 就积雪融化期叶绿素荧光活性持续时间而言, 与自然灌丛和移除50%灌丛相比, 完全移除灌丛的齿肋赤藓植株叶绿素荧光活性持续时间显著缩短。这可能是由于灌丛移除导致其UV-B辐射增加及“湿岛效应”消失所致, UV-B辐射的增加加剧了对植物的伤害, 而春季融雪期保水能力的下降也是其叶绿素荧光活性时间缩短的重要原因。     

Metabolic effects of thyroid hormones at a low temperature in the snake

1. 1.|The metabolic role of the thyroid gland was studied in intact snakes, Naja naja and Ptyas korros treated with tri-iodo-thyronine (T₃) and thyroxine (T₄) and in thyroidectomized (Tx) N. naja kept at 21°C by analyzing tissue composition and glycogen phosphorylase a activity.

2. 2.|Liver weight was unaffected by thyroid hormone injection in both species but decreases in liver glycogen followed T₃ or T₄ injection, and there was an increase in liver glycogen in N. naja. These changes in liver glycogen were accompanied by a decrease in glycogen phosphorylase a activity with T₃ injection. T₃ decreased muscle glycogen in Ptyas and Tx increased it in N. naja.

3. 3.|T₃ increased % liver lipid in Ptyas but not in Naja.

4. 4.|Between species, there were differences in liver weight, blood glucose level, cholesterol level and % muscle lipid.

5. 5.|The results showed that thyroid hormones affected carbohydrate and lipid metabolism at a low temperature of 21°C, although the significance is not known.

三峡库区消落带常见野生植物AM真菌

从三峡库区消落带3种常见野生植物的15个根际土壤样本中共分离鉴定出24种丛枝菌根真菌（Arbuscular mycorrhizal fungi,AMF）,包括球囊霉属Glomus 15种、无梗囊霉属Acaulospora 3种、近明球囊霉属Claroideoglomus 2种和多样孢霉属Diversispora、内养囊霉属Entro phospora、巨孢囊霉属Gigaspora及类球囊霉属Paraglomus各1种。其中地表多样孢囊霉D. epigaea 和伯氏类球囊霉P. pernambucanum是我国的新记录种。研究发现这3种植物根际土壤中丛枝菌根真菌的优势属为球囊霉属,优势种为地球囊霉G. geosporum、单孢球囊霉G. monosporum、地表球囊霉G. versiforme、副冠球囊霉G. coronatum 和黄孢球囊霉G. flavisporum。研究还发现在这3种植物根际土壤中丛枝菌根真菌的孢子密度平均为839±170个/100g土,物种丰富度在14-22种之间,Shannon-Wiener多样性指数和均匀度分别在1.97-2.21、0.409-0.479之间波动。结果表明三峡库区消落带是一个AMF多样性研究的资源库。