Recovery of bird communities after selective logging and clear-cutting in Kibale National Park,Uganda

In the face of the continuing destruction of tropical rainforests, a major challenge is to understand the consequences of these habitat changes for biodiversity and the time scale at which biodiversity can recover after such disturbances. In this study, we assessed the patterns in communities of birds among forests of varying age consisting of clear-cuts of former coniferous plantations, selectively logged compartments and primary forests in Kibale National Park, Uganda. Birds were surveyed by 10-minute point counts at 174 randomly located points in nine forest areas during September–October 2011. A total of 2 688 birds representing 115 species were recorded. The species density, diversity and dominance of all birds, and dominance of forest specialists showed no differences between forest areas, whereas the species density and diversity of forest specialists differed significantly between forest areas. The composition of communities of all birds and of forest specialists varied significantly among the forest areas. Our results show that even after 19 and 43 years, respectively, communities of birds in clear-cuts of former coniferous plantations and selectively logged forests have not fully recovered from the disturbances of logging, highlighting the need to preserve primary forests for conservation of birds.     

古田山常绿阔叶林主要树种2002-2007年间更新动态

种群更新是森林发育和演替过程中的重要环节.为了解古田山常绿阔叶林主要树种的更新动态,本研究以古田山自然保护区5 ha常绿阔叶林动态样地为对象,在对胸径(DBH)≥1 cm的木本植物个体2002年和2007年两次每木调查的基础上,比较主要树种的补员(recruitment)和死亡状况,分析种群大小变化趋势,研究了群落中主要木本植物的更新特点.结果表明:(1)5年间样地内木本植物个体从13,338株增长到16,812株,增幅达26.05%.新增4,758株胸径≥1 cm的补员个体,同时死亡1,384株.(2)乔木、小乔木或灌木、小灌木3种生长型的补员个体数目均随径级的增大而下降,但死亡个体却表现出不同的径级分布特点.(3)43个主要树种的平均年死亡率和年补员率分别为2.26%和5.90%.其中,19种小乔木或灌木在径级Ⅰ(1 cm≤DBH<2.5 cm)的补员率均高于死亡率,但径级Ⅱ(2.5cm≤DBH<5 cm)、径级Ⅲ(DBH≥5 cm)的补员率均和死亡率差别不大:而24种乔木各径级死亡率和补员率的关系则相对复杂.(4)43个主要树种中有31个为增长型种群,其余12个呈小幅度负增长.10个种群大小变化率在5%以上,属于快速变动的种群,其中以柳叶蜡梅(Chimonanthus salicifolius)(45.13%)和矩形叶鼠刺(Itea oblonga)(16.35%)的增幅最大,橙木(Loropetalum chinense)(-3.10%)和短柄袍(Quercus serrata vat.brevipetiolata)(-1.86%)的降幅最大.研究发现,3种生长型中,不同物种及其各个径级的补员率和死亡率各异,种群更新动态也有所差别,我们推测与密度制约和牛境波动有关.     

Inactivation of the MSLNL gene encoding mesothelin-like protein during African great ape evolution

Loss of gene function is implicated in the emergence of novel phenotypes during organism evolution. Here, we report the inactivation of the MSLNL gene encoding mesothelin-like protein in African great ape evolution. Human MSLNL has a nonsense mutation in exon 10 and two polymorphic mutations: a frameshift in exon 3 and a nonsense codon in exon 8. The gorilla gene also shows multiple deleterious mutations, including a premature stop codon, a deletion, and a splice site mutation. Molecular evolutionary analysis indicated relaxed selection pressure on MSLNL in African great ape lineages, which suggested that MSLNL might have become inactivated before the divergence of human, chimpanzee and gorilla. The mouse Mslnl gene is highly expressed in olfactory epithelium and moderately expressed in several other tissues. We propose that the loss of MSLNL may be associated with the evolution of the olfactory system in African great apes including human.     

云南哀牢山国家级自然保护区野生鸟兽的红外相机初步监测

红外相机技术目前已成为调查监测大中型兽类和地面活动鸟类的一种常规手段,在自然保护区物种资源编目中具有重要的应用价值。在2014年10月至12月期间,我们采用红外相机技术在云南哀牢山国家级自然保护区北部布设了40个相机位点,布设密度为1台/2 hm2,对中山湿性常绿阔叶林野生鸟兽进行了一次初步调查。相机累计工作1961个有效工作日,共获得野生动物独立有效照片566张,鉴定出隶属4目9科的10种兽类和2目4科的10种鸟类。相对丰富度指数较高的前2种兽类和3种鸟类分别为红颊长吻松鼠（Dremomys rufigenis）、野猪（Sus scrofa）和白鹇（Lophura nycthemera）、长尾地鸫（Zoothera dixoni）及斑背燕尾（Enicurus maculatus）。属于国家II级重点保护野生动物的有4种,被IUCN红色名录评估为“易危 VU”级别的物种有2种,列入CITES附录II和III的物种分别有2种和3种。本次调查仍有多种重要大中型兽类和鸟类未被记录,但是为保护区后续的野生动物红外相机常规监测和保护管理提供了基础信息。     

中坡国家森林公园蕨类植物区系分析

对中坡国家森林公园的蕨类植物分类、区系组成及其特点进行了研究．结果表明：中坡共有蕨类植物28科53属85种,主要科为鳞毛蕨科、水龙骨科、凤尾蕨科和金星蕨科;主要属为凤尾蕨属、鳞毛蕨属、耳蕨属和卷柏属;科的分布类型以世界分布和泛热带分布为主,属以泛热带属和热带亚洲属最多,种以东亚分布类型为主并表现出明显的亚热带特点;生态类型主要为土生,其次是石生类型．蕨类区系与贵州的关系最为密切．蕨类物种密度为每km^26．2种,在纬度相近的9个保护区中仅次于云南西山．中坡拥有桫椤和金毛狗等2种国家重点保护蕨类和7种中国特有的蕨类．桫椤在中坡的发现,对于研究其演变具有一定的意义．     

Fate and structure of DNA microinjected into mouse TK L cells

Co-microinjection of single linearized molecules of plasmids containing the human β-globin gene (pRK1) and the herpes simplex virus (HSV) type I thymidine kinase gene (pX1) into the mouse TK^? L cell nucleus results in covalent linkage between these (or derived) molecules within the nucleus as revealed by Southern blotting, plasmid rescue, and recovery of plasmid-derived DNA from a Charon 4A phage library of cellular DNA. The microinjected DNA is predominantly found as high molecular weight DNA as determined by Hirt fractionation. Southern blotting data and recombinants from the Charon 4A library suggest that the plasmid DNA is in the form of a head-to-tail linear concatamer of up to 80 copies. Passage of these microinjected cells in selective medium (HAT) results in coordinate amplification of both plasmids, which are maintained in an approx. 3:1 molar ratio of pRK1 to pX1-derived molecules. Hybridization in situ shows the DNA to be integrated on a translocation chromosome, t(4;4). Integration does not appear to be site-specific, since plasmid DNA from another microinjected cell line, C2B, appears on a different translocation chromosome, t(8?;14). Plasmid rescue experiments confirm a previous finding that passage of pBR322 DNA through eukaryotic cells may result in deletions of normally stable plasmid DNA upon subsequent transformation of E. coli. These deletions appear to occur in the bacteria, and originate in a 128 bp region between the Sal I and Hae II sites of pBR322.     

利用红外相机对湖南壶瓶山国家级自然保护区兽类和鸟类多样性的初步调查

2012年8月至2015年8月,在壶瓶山国家级自然保护区布设了20个红外相机监测公里网格,对保护区的兽类和鸟类多样性进行了初步调查。经过19,592个有效相机工作日的调查,共记录到兽类4目11科21种和鸟类4目8科33种,其中有国家Ⅰ级重点保护野生动物1种（林麝 Moschus berezovskii）、国家Ⅱ级重点保护野生动物8种和保护区新纪录兽类1种（红腿长吻松鼠Dremomys pyrrhomerus）。兽类以食肉目种类最多（9种）,其次为鲸偶蹄目（6种）和啮齿目（5种）。毛冠鹿（Elaphodus cephalophus）、野猪（Sus scrofa）、红腿长吻松鼠、小麂（Muntiacus reevesi）和猪獾（Arctonyx collaris）的相对丰富度居于兽类的前5位。鸟类以雀形目的种类最多（25种）,其次是鸡形目（5种）和鴷形目（2种）。红腹锦鸡（Chrysolophus pictus）、红腹角雉（Tragopan temminckii）和眼纹噪鹛（Garrulax ocellatus）的相对丰富度指数居于鸟类的前3位。此外,本文对红腹锦鸡、红腹角雉、红腿长吻松鼠、毛冠鹿、野猪和小麂等常见物种的日活动节律和年活动节律进行了初步分析。本次调查初步了解了保护区内地栖大中型兽类和鸟类的本底信息,为保护区今后开展野生动物长期监测提供了重要依据。     

Solution Structure and Phospholipid Interactions of the Isolated Voltage-Sensor Domain from KvAP

Voltage-sensor domains (VSDs) are specialized transmembrane segments that confer voltage sensitivity to many proteins such as ion channels and enzymes. The activities of these domains are highly dependent on both the chemical properties and the physical properties of the surrounding membrane environment. To learn about VSD-lipid interactions, we used nuclear magnetic resonance spectroscopy to determine the structure and phospholipid interface of the VSD from the voltage-dependent K⁺ channel KvAP (prokaryotic Kv from Aeropyrum pernix). The solution structure of the KvAP VSD solubilized within phospholipid micelles is similar to a previously determined crystal structure solubilized by a nonionic detergent and complexed with an antibody fragment. The differences observed include a previously unidentified short amphipathic α-helix that precedes the first transmembrane helix and a subtle rigid-body repositioning of the S3-S4 voltage-sensor paddle. Using ¹⁵N relaxation experiments, we show that much of the VSD, including the pronounced kink in S3 and the S3-S4 paddle, is relatively rigid on the picosecond-to-nanosecond timescale. In contrast, the kink in S3 is mobile on the microsecond-to-millisecond timescale and may act as a hinge in the movement of the paddle during channel gating. We characterized the VSD-phospholipid micelle interactions using nuclear Overhauser effect spectroscopy and showed that the micelle uniformly coats the KvAP VSD and approximates the chemical environment of a phospholipid bilayer. Using paramagnetically labeled phospholipids, we show that bilayer-forming lipids interact with the S3 and S4 helices more strongly than with S1 and S2.     

Trophic interactions among invertebrates in termitaria in the African savanna: a stable isotope approach

Abstract 1. Termites (Isoptera) in tropical savannas are known as ecosystem engineers, affecting the spatial and temporal distribution of water, carbon, cations, and nutrients through their mound structures. Their mounds, however, also offer habitation to diverse taxa and feeding guilds of other invertebrates; a keystone role that has not been properly quantified. 2. The aim of this study was to explore the ecosystem role of termitaria in determining invertebrate diversity and their potential trophic interactions. We used stable isotopes to distinguish termite‐feeding invertebrates from invertebrates merely living in termite mounds under field conditions. 3. The results suggest that inquiline spiders (Arachnida) do not feed on termites directly, but on other invertebrates within the termitaria that are termitophagous, elevating the spiders three trophic levels higher than the termites. 4. This study is the first to demonstrate food web interactions among inquiline invertebrates with a stable isotope approach. It provides evidence that termites play a keystone role in the system by providing habitat for various, trophically interacting invertebrates. These results illustrate a rather unexplored ecosystem property of savanna termites.