广西弄岗黑叶猴栖息地选择与利用

2005年9月至2006年8月对广西弄岗国家自然保护区内一群黑叶猴进行行为观察,采用瞬时扫描法观察并收集猴群的栖息地利用数据,分析黑叶猴对喀斯特石山栖息地的选择与利用规律。结果表明,黑叶猴对不同山体部位的利用有显著性差异(χ~2=43.063,df=4,P0.001)。黑叶猴对崖壁的利用频率最高(占总记录的36.67%±9.44%),其次是山坡(32.30%±9.57%),对山脚(14.15%±5.01%)、山顶(11.24%±8.42%)和平地(5.63%±2.92%)的利用较少。分析发现,黑叶猴对山体部位的利用没有显著的季节性差异(山顶:Z=-0.160,P=0.837;崖壁:Z=-0.320,P=0.749;山坡:Z=-0.480,P=0.631;山脚:Z=-1.601,P=0.109;平地:Z=0,P=1)。黑叶猴将崖壁作为主要的休息场所,山坡和山脚为主要的移动和觅食场所。黑叶猴对栖息地的利用受食物可获得性的影响。当食物中花的可获得性降低时,猴群增加对山脚的利用;当嫩叶可获得性降低时,猴群增加在崖壁移动的频率;当果实的可获得性升高时,猴群增加在平地觅食的频率。食物组成与黑叶猴栖息地利用也有关系。总体来看,黑叶猴对山顶的利用频率与花的觅食比例呈显著正相关;对山脚的利用频率与果实+种子的觅食比例呈显著正相关。猴群在山顶休息的频率随花和成熟叶的觅食比例的上升而上升;在山脚休息的频率随果实+种子的觅食比例的上升而上升。猴群在山坡觅食的频率随果实+种子的觅食比例的下降而上升;在山脚觅食的频率随嫩叶的觅食比例的下降而上升。另外,平均最低温度与猴群在平地觅食的频率呈负相关关系。分析表明食物的分布和数量对黑叶猴栖息地利用有重要影响,黑叶猴对栖息地的选择是在觅食利益与风险之间进行权衡的结果。     

皮氏菊头蝠(Rhinolophus pearsoni)的栖息生态特征

皮氏菊头蝠(Rhinolophus pearsoni)是我国南方典型的洞栖食虫性蝙蝠,具有重要的生态意义。近年于湘西州及张家界市的25个溶洞中共记录到该蝠450只次,对其栖息生态特征(空间分布、姿势、体温、栖点温度和栖点安全性等)进行了较为系统的观测。结果表明:该蝠的栖点主要集中分布于离洞口440 m之内的洞段(占99.3%),栖点高度通常介于2—10 m之间(84%),主要采取双足倒挂的姿势栖息于洞顶壁或侧壁,但单足倒挂的栖息姿势也较为常见(36.2%)。体温介于10.7—25.2℃,体温总是稍高于栖点温度,但两者之间无显著性差异(P0.05),且两者呈线性正相关。约64%的栖点"安全性高",而"安全性低"和"安全性中"的栖点分别占17.6%和18.4%。减少对洞穴的人为干扰是保护该物种的有效途径。     

喀斯特次生林幼树更新空间分布格局及种间关联性

本研究以贵州省喀斯特典型区域紫云苗族布依族自治县撂荒30余年后自然恢复形成的次生林为对象,设置140 m×120 m固定样地,系统调查样地内幼树更新,并采用空间点格局分析方法分析幼树更新优势种群在不同空间尺度下的分布格局和种间关联性。结果表明: 调查样地中幼树共计1291株,包括39个树种,其中光皮桦、化香、马尾松、枫香和山杨5个树种的幼树个体数量总和达83.7%,重要值总和达77.8%,为幼树更新的优势树种。光皮桦、化香和枫香3个幼树优势种群的空间分布格局在0～60 m空间尺度上均呈现较强的聚集分布;马尾松和山杨2个幼树优势种群在小尺度上呈现聚集分布,大尺度上则随机分布。幼树优势种群空间关联性多呈现正关联,仅马尾松与枫香和山杨在小尺度呈现正关联,大尺度呈现不相关。调查样地5个幼树优势种群空间分布格局及种间关联性差别较大,可能与树种的生物学特性、生境及空间资源的利用密切相关。目前,林分多以先锋树种为主,群落结构不稳定;以马尾松和光皮桦为优势种群的松-桦混交林可能成为下一阶段演替方向,建议通过森林经营措施加快植被恢复进程。     

Gut microbiomes of sympatric Amazonian wood‐eating catfishes (Loricariidae) reflect host identity and little role in wood digestion

Neotropical wood‐eating catfishes (family Loricariidae) can occur in diverse assemblages with multiple genera and species feeding on the same woody detritus. As such, they present an intriguing system in which to examine the influence of host species identity on the vertebrate gut microbiome as well as to determine the potential role of gut bacteria in wood digestion. We characterized the gut microbiome of two co‐occurring catfish genera and four species: Panaqolus albomaculatus, Panaqolus gnomus, Panaqolus nocturnus, and Panaque bathyphilus, as well as that of submerged wood on which they feed. The gut bacterial community did not significantly vary across three gut regions (proximal, mid, distal) for any catfish species, although interspecific variation in the gut microbiome was significant, with magnitude of interspecific difference generally reflecting host phylogenetic proximity. Further, the gut microbiome of each species was significantly different to that present on the submerged wood. Inferring the genomic potential of the gut microbiome revealed that the majority of wood digesting pathways were at best equivalent to and more often depleted or nonexistent within the catfish gut compared to the submerged wood, suggesting a minimal role for the gut microbiome in wood digestion. Rather, these fishes are more likely reliant on fiber degradation performed by microbes in the environment, with their gut microbiome determined more by host identity and phylogenetic history.     

Neumark-Nord 2 – A multiphase Middle Palaeolithic open-air site in the Geisel Valley (Central Germany)

The lake basin Neumark-Nord 2 (NN 2) is located in the Geisel Valley in Saxony-Anhalt (Germany). It was scientifically investigated between 2003 and 2008. The sediment sequence, which is about 10 to 11 m thick, consists of limnic deposits, mostly silts mixed with clays and sands. Sedimentological as well as palynological, malacological and palaeomagnetic investigations, supported by absolute datings, date the entire sequence into the Eemian and Early Weichselian. Within the deposits several archaeological find horizons were discovered. Neumark-Nord 2/2 (NN 2/2) at the beginning of the Eemian and Neumark-Nord 2/0 (NN 2/0) with an early Weichselian were the most important archaeological horizons. Both find horizons represent former lake shore sites, where numerous crushed animal bones and other faunal debris were found, which can be regarded as remains of hunted game. With regard to the rich lithic material, both find horizons differ remarkably. In NN2/2, a simple artefact spectrum with a certain Levallois component and a dominance of denticulated, notched and laterally retouched specimens. In NN 2/0, on the other hand, bifacial tools such as backed knives and sometimes finely retouched scrapers are dominant, while the Levallois component fades completely into the background. Thus, NN 2 is one of the few open-air sites in archaeological landscape of Central German where several middle Palaeolithic find horizons occur in superposition.     

Congruent spatial patterns of species richness and phylogenetic diversity in karst flora: Case study of Primulina (Gesneriaceae)

The karst landform in southern China is renowned for its high levels of species diversity and endemism. Globally, karst ecosystems are under threat from unsustainable anthropogenic disturbance and climate changes and are among the most threatened ecosystems worldwide. In this study, we used the typical karst endemic genus in southern China, Primulina Hance, as a model to identify areas within the karst landform with high diversity and to investigate congruence between phylogenetic and species‐based measures of diversity. Using phylogenetic information and species distribution data, we measured geographical patterns of diversity with four metrics: species richness (SR), corrected weighted endemism (CWE), phylogenetic diversity (PD), and phylogenetic endemism (PE). Our results revealed a high spatial congruence among SR, PD, and PE, with hotspot areas identified in the Nanling Mountains (i.e., north Guangdong and northeast Guangxi) and southeast Yungui Plateau (i.e., north and southwest Guangxi), whereas the hotspots of CWE are comparatively uniform throughout the geographic extent. The categorical analysis of neo‐ and paleoendemism identified a pattern of mixed neo‐ and paleoendemism in numerous grid cells, suggesting that karst areas in southern China have acted as both “museums” and “cradles” of plant evolution. Conservation gap analysis of hotspots revealed that the majority of prioritized hotspots (>90%) of the genus are outside of protected areas, therefore indicating the limited effectiveness of national nature reserves for the karst flora. Overall, our results suggest that the karst flora merits more conservation attention and SR can be an effective surrogate to capture PD in conservation planning.     

隐匿性胫骨平台骨折MRI、CT检查的影像学表现及其诊断价值对比的回顾性研究

目的:研究对比隐匿性胫骨平台骨折(TPOF)磁共振成像(MRI)、电子计算机断层扫描(CT)检查的影像学表现及其诊断价值。方法:回顾性分析我院自2016年1月至2019年12月拟诊断为TPOF且X线检查表现为阴性的89例患者的临床资料,分别对所有受试者进行MRI、CT检查,且以手术检查为金标准,比较上述两种影像学检查手段诊断TPOF的效能。此外,比较MRI、CT检查诊断TPOF的表观扩散系数以及节段各向异性值以及对TPOF类型的检出率。结果:MRI检查诊断TPOF的灵敏度、特异度及准确度分别为98.61%、94.12%、97.75%,均高于CT检查的79.17%、64.71%、76.40%(均P<0.05)。MRI检查诊断TPOF的表观扩散系数高于CT检查,而节段各向异性值低于CT检查(均P<0.05)。MRI检查对骨皮质骨折的检出率低于CT检查,而对骨小梁骨折的检出率高于CT检查(均P<0.05)。结论:MRI检查诊断TPOF的价值高于CT检查,且在骨小梁骨折的检出率方面优于CT检查,但CT检查应用于骨皮质骨折的诊断价值更高。临床工作中可能通过联合MRI以及CT检查,继而达到提高TPOF检出率的目的。     

Individual dispersal,landscape connectivity and ecological networks

Connectivity is classically considered an emergent property of landscapes encapsulating individuals' flows across space. However, its operational use requires a precise understanding of why and how organisms disperse. Such movements, and hence landscape connectivity, will obviously vary according to both organism properties and landscape features. We review whether landscape connectivity estimates could gain in both precision and generality by incorporating three fundamental outcomes of dispersal theory. Firstly, dispersal is a multi‐causal process; its restriction to an ‘escape reaction’ to environmental unsuitability is an oversimplification, as dispersing individuals can leave excellent quality habitat patches or stay in poor‐quality habitats according to the relative costs and benefits of dispersal and philopatry. Secondly, species, populations and individuals do not always react similarly to those cues that trigger dispersal, which sometimes results in contrasting dispersal strategies. Finally, dispersal is a major component of fitness and is thus under strong selective pressures, which could generate rapid adaptations of dispersal strategies. Such evolutionary responses will entail spatiotemporal variation in landscape connectivity. We thus strongly recommend the use of genetic tools to: (i) assess gene flow intensity and direction among populations in a given landscape; and (ii) accurately estimate landscape features impacting gene flow, and hence landscape connectivity. Such approaches will provide the basic data for planning corridors or stepping stones aiming at (re)connecting local populations of a given species in a given landscape. This strategy is clearly species‐ and landscape‐specific. But we suggest that the ecological network in a given landscape could be designed by stacking up such linkages designed for several species living in different ecosystems. This procedure relies on the use of umbrella species that are representative of other species living in the same ecosystem.     

后侧手术入路、锁定钢板固定治疗胫骨平台后髁骨折的临床疗效

目的：探讨采用膝关节后内和后外侧切口、锁定钢板固定治疗胫骨平台后髁骨折的临床疗效。方法：选取2009年1月～2011年12月来我院治疗的13例胫骨平台后髁骨折患者作为研究对象,所有患者采用后内和后外侧切口、锁定钢板固定治疗,观察术后骨折愈合情况,采用Rasmussen放射学评分评定骨折复位情况,采用HSS评分系统评定膝关节功能疗效。结果：术后随访6～24个月,平均13．6个月,所有患者骨折均于16周内愈合。Rasmussen放射学评分15～18分,平均17．4分,其中优8例,良3例,可2例,优良率为84．7％。末次随访时膝关节功能HSS评分73~97分,平均91．4分,其中获优7例,良5例,可1例,优良率为92．3％。结论：采用膝关节后内和（或）后外侧切口、锁定钢板固定治疗胫骨平台后髁骨折具有操作简单、显露清晰、直视下复位骨折及关节面、固定牢靠、利于早期功能锻炼、临床疗效确切、并发症少等优点。