白杨派杂种无性系生根特性研究

通过对采用杂交育种方法选育出的白杨无性系生根性状进行研究。结果表明,新无性系在最早生根时间、主侧根总数量、主侧根总长度等指标上均存在极显著差异,说明各无性系的生根能力具有显著差异。主根平均根数和侧根平均根数两个性状的遗传方差均大于环境方差,其重复力分别可达95％和87％。进一步分析结果表明易生根的无性系根原基数量最多,平均每段插穗约14．7～7．3个．而较难生根的无性系平均每段插穗约5．5～6．8个,难生根的毛白杨根原基数量最少,平均每段插穗约3．3个。通过层次分析法(AHP)对各无性系生根特性的综合评价结果表明：9606、9603、9608、9607、9614、9610、9602等7个无性系生根能力均优于其亲本和毛白杨。     

Biological hierarchies and the nature of extinction

Hierarchy theory recognises that ecological and evolutionary units occur in a nested and interconnected hierarchical system, with cascading effects occurring between hierarchical levels. Different biological disciplines have routinely come into conflict over the primacy of different forcing mechanisms behind evolutionary and ecological change. These disconnects arise partly from differences in perspective (with some researchers favouring ecological forcing mechanisms while others favour developmental/historical mechanisms), as well as differences in the temporal framework in which workers operate. In particular, long‐term palaeontological data often show that large‐scale (macro) patterns of evolution are predominantly dictated by shifts in the abiotic environment, while short‐term (micro) modern biological studies stress the importance of biotic interactions. We propose that thinking about ecological and evolutionary interactions in a hierarchical framework is a fruitful way to resolve these conflicts. Hierarchy theory suggests that changes occurring at lower hierarchical levels can have unexpected, complex effects at higher scales due to emergent interactions between simple systems. In this way, patterns occurring on short‐ and long‐term time scales are equally valid, as changes that are driven from lower levels will manifest in different forms at higher levels. We propose that the dual hierarchy framework fits well with our current understanding of evolutionary and ecological theory. Furthermore, we describe how this framework can be used to understand major extinction events better. Multi‐generational attritional loss of reproductive fitness (MALF) has recently been proposed as the primary mechanism behind extinction events, whereby extinction is explainable solely through processes that result in extirpation of populations through a shutdown of reproduction. While not necessarily explicit, the push to explain extinction through solely population‐level dynamics could be used to suggest that environmentally mediated patterns of extinction or slowed speciation across geological time are largely artefacts of poor preservation or a coarse temporal scale. We demonstrate how MALF fits into a hierarchical framework, showing that MALF can be a primary forcing mechanism at lower scales that still results in differential survivorship patterns at the species and clade level which vary depending upon the initial environmental forcing mechanism. Thus, even if MALF is the primary mechanism of extinction across all mass extinction events, the primary environmental cause of these events will still affect the system and result in differential responses. Therefore, patterns at both temporal scales are relevant.     

基于层次分析法的江苏宁镇山脉乡土树种评价

为了筛选适宜南京地区的优良城市绿化树种,在野外调查和问卷调查的基础上,利用层次分析法(AHP)建立江苏宁镇山脉乡土树种评价体系,对该区域的乡土树种进行客观的定量分析。结果表明:(1)乡土树种作为城市绿化树种应首先考虑抗逆性,其次是生态价值、美学价值和生物学特性;(2)参与评价的41种宁镇山脉乡土树种可分为4类,其中I类乡土树种应大力推广应用,Ⅱ类乡土树种可作为森林城市树种多样性的有益补充,Ⅲ类和Ⅳ类乡土树种作为城市绿化树种仍有一定的差距。13种Ⅰ类乡土树种作为城市绿化树种具有良好的应用前景。     

2010-2019年不同海湾迁徙水鸟栖息地适宜性变化对比研究

滨海湿地是迁徙水鸟的重要迁飞通道和主要栖息地,评估沿海迁徙水鸟栖息地适宜性及变化态势能为栖息地的合理规划与管理提供科学参考,对迁徙水鸟的保护有重要意义。选择紧邻城市和乡村的深圳湾和雷州湾为研究区,在水鸟栖息地生态系统类型分类的基础上,通过层次分析法确定水鸟栖息地适宜性评价因子,设计栖息地、食物、水分、人类干扰条件及其子类的权重,对栖息地适宜性进行等级划分,分析比较2010-2019年迁徙水鸟栖息地适宜性的时空分布差异,探索适宜性变化差异的原因并给出合理化建议。结果表明：（1）2010-2019年深圳湾有193.4 hm²强干扰区域转变化为中等及弱干扰;雷州湾有16.36 hm²的中等干扰转化为弱、无干扰;（2）深圳湾栖息地适宜性以中等适宜类型为主,2010年和2019年面积占比分别为83.74%和88.71%;雷州湾栖息地适宜性主要以较适宜和中等适宜类型为主,2010年面积占比为86.72%,2010-2019年面积占比基本不变,总体适宜性高于深圳湾。（3）2010-2019年,深圳湾不适宜和较适宜面积分别减少245.54 hm²和26.37 hm²,均转化为中等适宜类型;雷州湾有24.31 hm²的中等和较适宜栖息地转化为适宜类型。     

Behavioural and chemical mechanisms behind a Mediterranean ant–ant association

1. Interspecific competition among ants is common, and so is competitive exclusion among dominant ant species. In contrast, specific associations between non‐parasitic ant species are rare, especially in the temperate zones. As an exception, the subordinate ant Camponotus lateralis frequently co‐occurs with the dominant Crematogaster scutellaris but rarely with other dominant ants. 2. This association is one of various associations between Camponotus and Crematogaster species across the world. However, the mechanisms behind these co‐occurences are largely unknown. 3. In the present study, we therefore investigated the association of Ca. lateralis and Cr. scutellaris. We studied the spatial association of the nests, interspecific aggression, both species' cuticular hydrocarbon profiles, and their propensity to follow the other species' pheromone trails. 4. Crematogaster scutellaris usually attacked and displaced the generally submissive Ca. lateralis, but was significantly less aggressive at jointly used trails. Camponotus nests were always in close proximity to Crematogaster nests. 5. The cuticular hydrocarbons of both species consisted of alkanes with chain lengths between C21 and C35. The two species had 25 hydrocarbons in common, including mono‐, di‐, and tetramethyl alkanes. Despite this qualitative similarity, however, the quantitative hydrocarbon composition differed between the two species. 6. Camponotus lateralis followed artificial trails containing trail pheromones of Cr. scutellaris, but the latter did not follow Ca. lateralis trail pheromones. Interspecific trail‐following by Camponotus, but not vice versa, has been observed in another Camponotus–Crematogaster association and may be a more general mechanism that facilitates associations between the two ant genera.     

Changes in ranging and agonistic behavior of vervet monkeys (Cercopithecus aethiops) after predator‐induced group fusion

Socio‐ecological theory predicts that group fusion in female‐philopatric primate species will be rare because females experience increased costs by associating with non‐relatives. Indeed, fusion has been reported only 14 times in only 4 female‐philopatric cercopithecines despite many years of observation. Here, we describe changes in ranging and agonistic behavior of vervet monkeys (Cercopithecus aethiops) after the fusion of two groups, the sole group fusion during 11 years of observation, induced by a brief but intense period of apparent leopard predation. Before fusion, both groups made few incursions into the other group's territory and spent most of the time in their own territories. After the fusion, the amalgamated group shifted its activities and used both territories in similar proportion. Rates of female agonism increased after fusion, particularly in the 2 weeks following fusion, and the small group females assumed the lowest ranks in the female dominance hierarchy. Rates of agonism returned to prefusion rates a month later. Although rates of high‐intensity interactions (i.e., chases) did not increase after fusion, small group females were more likely to be the recipients of, and lose, agonistic interactions than large group females; a small group female and her infant were attacked and wounded by a coalition of large group females shortly after the fusion. The observations presented here reveal that the circumstances surrounding group fusions are more variable than previously realized, but are still in accordance with expectations from socio‐ecological theory that predation can favor the formation of larger groups. In this case, under threat of severe predation, individuals may have surrendered group autonomy for the greater security of larger numbers. Am. J. Primatol. 72:634–644, 2010. © 2010 Wiley‐Liss, Inc.     

基于SSR标记的不同优势等级云南松遗传多样性分析

基于SSR分子标记技术,按树高和胸径（地径）因子将样地内的植株分为优势木、中等木和劣势木3类,对不同生长优势等级云南松林木的遗传多样性变异特征进行了研究。结果表明：在林冠层,优势木的有效等位基因数、Shannon's信息指数、观测杂合度和期望杂合度分别为2.083、0.762、0.290和0.423,略高于中等木和劣势木;在更新层,有效等位基因数、Shannon's信息指数、观测杂合度和期望杂合度分别为2.063、0.774、0.272和0.410,除观测杂合度外,其余3个指标也均表现为优势木略高于中等木和劣势木。从差异显著性检验来看,不同生长优势等级云南松林木间的遗传多样性差异不显著,即林木生长分化对遗传多样性的影响不明显。     

Establishment of a Captive All‐male Group of Proboscis Monkey (Nasalis larvatus) at the Singapore Zoo

Surplus male proboscis monkeys at the Singapore Zoo pose a considerable problem for maintenance and maximizing of exhibition potential. In 2008, a new exhibit was constructed to house and display a group of six proboscis monkey males born in Singapore Zoo. To document and monitor the all‐male group establishment in the new exhibit, we conducted observations on intragroup interactions between the monkeys, spatial use of their new exhibit, and visitor effects on their behavior. We found contact aggressive interactions between the monkeys to be consistently lower than noncontact aggressive interactions and by week six of introduction to the new exhibit, contact aggression was almost nonevident. Affiliative interactions also developed between individuals in the group, with an interface of aggressive and socioreconcilatory behavior influenced by food competition and a dominance hierarchy. This was evident from significantly higher overall aggression and affiliation during feeding times compared to nonfeeding times, and this was reduced when food competition was mitigated by modifying the feeding regime. We measured the groups’ spatial use of the exhibit and the relation to behavior, crowd size, and density. Our results showed that the proboscis monkeys utilized the available exhibit space, were largely unaffected by visitor crowd size and density, and were able to exhibit a variety of natural behaviors, including swimming. Our accomplishment in maintaining and displaying an all‐male group of proboscis monkeys in captivity provides viable options for more comprehensive captive management and breeding programs for this endangered species. Zoo Biol. 32:281‐290, 2013. © 2012 Wiley Periodicals, Inc.     

Risk Assessment of Transgenic Virus-resistant White Clover: Non-target Plant Community Characterisation and Implications for Field Trial Design

One of the most difficult elements of the ecological risk assessment of transgenic plants is investigation of their potential impact on biodiversity in complex non-target communities. This problem is particularly acute for pasture plants, since many have a track record of invasiveness. In this paper we develop an understanding of some aspects of the ecology of Trifolium repens L. (white clover) in montane vegetation communities in southeastern Australia as part of a larger project investigating potential ecological risks associated with commercial release of newly-developed transgenic virus-resistant T. repens cultivars. We use a combination of floristic surveys and biomass sampling to determine the habitat affinity of T. repens, the structure and composition of associated communities, and the scale at which different abiotic and biotic factors correlate with T. repens abundance. We also compare the abundance of native and exotic species within specific morpho-functional groups and use this to determine the relative significance of T. repens as a community constituent, and to identify native species that would be most at risk by expanding populations of T. repens. We found that T. repens comprises a relatively small component of the total community cover and biomass, but is one of the most abundant herbaceous species in mesic Poa – dominated grasslands and Poa-Eucalyptus woodlands in the study area, and that T. repens abundance is correlated at the within-community scale primarily with soil moisture and fertility. At smaller scales T. repens is limited by the hierarchical dominance of native graminoids and we conclude that competition for inter-tussock space in mesic communities is the most likely mechanism by which expanding populations of T. repens would influence populations of associated native species. These results have significant implications for the manner in which future analysis and risk quantification stages of the risk assessment of virus-resistant T.␣repens and other transgenic pasture plants in complex plant communities are performed.     

Do battles lead to coexistence? Role of interference competition in structuring the insect community on fermented tree sap

Abstract.  1. In insect communities on fermented tree sap, agonistic interactions occur frequently among the component species. This study examined the effects of such interference competition on community structure and species co-occurrence on a spatio-temporally small scale.
2. Experimental removal of giant hornets ( Vespa mandarinia ), one of the most dominant species, showed no effect on either species richness or total abundance of the remaining insects. Significant increases in abundance were detected for five out of 19 taxa: V. ducalis , V. crabro , Lasius japonicus , Cryptarcha lewisi , and a group of micro sap beetles ( Epuraea spp., Haptoncus spp., and Haptoncurina spp.).
3. Behavioural observations indicated that interference did not alter the staying time at a patch (an exuding spot on a tree) for V. mandarinia , Rhomborrhina japonica , and Neope goschkevitschii . Interference-mediated departure from a patch was less frequent than departure without interference for all nine species observed, except for R. japonica . These behavioural contexts varied yearly for several species.
4. These results suggest that interference competition is a minor determinant of overall community structure, despite its conspicuousness. This weak effect of interference may be attributed to the short stay of dominant species and to individual behavioural responses, such as competitor avoidance. The variable influence of interference might be related to differences in species attributes, such as dominance hierarchies.