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931.
The body shape of a species is associated with its evolutionary history and can reflect behavioural peculiarities related to the ecological niche of each species. Morphology can characterise the morphometric niche of species and can be represented as body shape points within a morphometric universe. This information can be to calculate the morphometric diversity of communities through hypervolume metrics, and the hole sizes that remain in the morphometric hypervolume, which are empty areas with no species. Such holes may be ‘natural’ or caused by a local extinction. In this study, we evaluate the ecological community of dung beetles through the lens of morphometric diversity. We evaluated 38 dung beetle species from 30 subtropical communities in southern Brazil sampled in the summer of 2015, including 15 forest remnant communities from the Atlantic Forest and 15 communities from adjacent maize cultivations. The shape of 495 dung beetle specimens was measured using geometric morphometric and hypervolume techniques to calculate the morphometric diversity and the hole size of each of the 30 communities. We found that the taxonomic diversity positively correlated with the morphometric diversity and negatively correlated with the size of the holes. We also found that forest communities had higher values of morphometric diversity and smaller holes in the hypervolume than the maize cultivation communities, suggesting that local extinction may reduce community body shape spaces.  相似文献   
932.
Preserving species diversity is critical to ensure ecosystem functioning; however, different components of diversity might respond to human disturbance in different ways. Similarly, trophic levels might have uncoupled responses to the same disturbance, thus ameliorating or aggravating the persistence of ecological communities. In this study, we analysed how the density, richness and evenness of flowers and pollinators respond to four levels of woodland thinning intensity (0, 30, 50 and 70% of woodland basal area removed) over 2 years in three contrasting sites. We found a mismatch in the response of flowers and pollinators to thinning. Flower density and richness had disparate responses, depending on the site and year, while evenness did not change with thinning. In contrast, pollinator density and richness, but not evenness, consistently increased with thinning among years and sites. These results suggest that thinning has a great influence on pollinators through changes in abiotic conditions and, perhaps, flower attractiveness rather than through small‐scale changes in flower density and richness. At the site where tree flowers were absent, bee pollinator community composition was impoverished, suggesting that trees provide important floral resources to pollinators. Our findings indicate that disturbance may diminish local plant abundance and richness, but pollinator abundance and richness are enhanced after intense thinning at small scales.  相似文献   
933.
Vertebrates usually reproduce sexually in which males and females contribute their offspring genome and produce genetically diverse offspring. However, some of them are asexual without genetic contribution from males. The nocturnal gecko, Lepidodactylus lugubris, is all females and reproduces parthenogenetically. This gecko is known to consist of diploid and triploid clones in the tropical and subtropical regions, which can be identified by their dorsal marking patterns, ploidy, and protein polymorphism. This gecko is also distributed in the southern parts of Japan, and several clones have been reported. In this study, we investigated the origins and genetic diversity of Japanese L. lugubris by clonal discrimination using microsatellite and mitochondrial DNA analyses. A total of 748 individuals were collected from 21 islands of five island groups (Ogasawara, Okinawa, Miyako, Yaeyama and Daito Islands) and 17 clones were distinguished genetically. Mitochondrial cyt b sequences of these clones suggested that they were all closely related and differentiated recently. Clonal diversity was much higher (14 clones) in the Daito Islands than in the other island groups in which only one or two clones coexisted. Judging from the dorsal marking patterns and ploidy known so far, six clones were cosmopolitan and may be colonized from the outside of Japan. However, other 11 clones were endemic to the Daito Islands and explained by possible hybridization between the one female diploid clone and one male diploid clone because other 9 clones were triploid and all had the combinations of polymorphic microsatellite alleles of these female and male diploid clones. Although the males have never been recorded in the Daito Islands, males might appear in the past. These findings contribute to understanding of clonal diversity and dynamics of asexually reproducing animals. If diploid parthenogenetic geckos can produce triploid clones by mating with the diploid males, clonal diversity would increase rapidly in a small island, and such newly produced triploid clones would expand widely.  相似文献   
934.
935.
为证明大胡蜂Vespa magnifica(Smith)蜂毒具有较大的药用开发价值,本研究采用超高效液相色谱-质谱和电泳技术对其多肽和蛋白质的分布进行分析,发现其蛋白质的相对分子质量主要分布在17~45kDa范围内。蜂毒多肽类物质的相对分子质量呈"单峰"式分布,61%在500~3000Da范围内,为大胡蜂蜂毒中多肽含量最为丰富的部分。通过牛津杯法对蜂毒的抑菌活性进行研究,且以HepG2人肝癌细胞及B16黑色素瘤细胞为研究对象,用MTT法检测蜂毒的细胞毒性活性,证明其具有良好的抑菌作用和细胞毒活性,其结果与已报道的其他蜂类既有相似性又存在具体差异,展示了大胡蜂蜂毒的分子多样性,为后续该毒素的物质基础研究及药用价值开发提供参考。  相似文献   
936.
红外相机监测是了解野生动物多样性和威胁因素的重要手段。本研究采用网格法和分层抽样调查法, 在贵州赤水桫椤国家级自然保护区内选取20个监测位点布设红外相机, 对区内鸟兽物种多样性进行监测。2015年8月至2017年8月, 红外相机累计工作6,370个工作日, 共拍摄45,953张照片, 独立有效照片1,936张。准确鉴定出兽类4目8科19种, 鸟类4目11科28种, 其中, 国家II级重点保护野生动物7种。相对丰富度指数(RAI)排前五位的兽类依次是毛冠鹿(Elaphodus cephalophus)、鼬獾(Melogale moschata)、藏酋猴(Macaca thibetana)、小麂(Muntiacus reevesi)和野猪(Sus scrofa); 鸟类依次是紫啸鸫(Myophonus caeruleus)、红腹角雉(Tragopan temminckii)、灰胸竹鸡(Bambusicola thoracicus)、黑喉噪鹛(Garrulax chinensis)和棕颈钩嘴鹛(Pomatorhinus ruficollis)。物种积累曲线结果表明, 兽类稀疏化曲线在300天后趋于稳定, 表明监测取样已较充分, 而鸟类监测物种数随时间积累依旧保持增长趋势。  相似文献   
937.
红外相机监测是了解野生动物多样性现状、动态变化和面临威胁的重要手段。本研究采用网格抽样调查法, 在贵州梵净山国家级自然保护区内选取2个监测样区共40个监测位点布设红外相机, 对区内兽类和鸟类物种进行监测调查。2017年4月至2018年12月间, 红外相机累积监测14,808个相机工作日, 共收集有效照片14,119张, 独立有效物种照片3,199张。共鉴定野生动物9目22科61种, 其中兽类26种, 隶属于4目12科; 鸟类35种, 隶属于5目10科。记录到国家I级重点保护野生动物2种: 黔金丝猴(Rhinopithecus brelichi)和白颈长尾雉(Syrmaticus ellioti), 国家II级重点保护野生动物9种; 被IUCN红色名录评估为濒危(EN)的1种、易危(VU)的5种、近危(NT)的8种。物种的相对多度指数(relative abundance index, RAI)分析结果显示, 藏酋猴(Macaca thibetana, RAI = 28.23)、毛冠鹿(Elaphodus cephalophus, RAI = 15.46)、野猪(Sus scrofa, RAI = 11.82)、小麂(Muntiacus reevesi, RAI = 9.05)、黔金丝猴(RAI = 7.70)为相对多度最高的5种兽类; 紫啸鸫(Myophonus insularis, RAI = 10.33)、红腹角雉(Tragopan temminckii, RAI = 9.59)、红腹锦鸡(Chrysolophus pictus, RAI = 6.96)、白颈长尾雉(RAI = 3.71)、勺鸡(Pucrasia macrolopha, RAI = 1.55)为相对多度最高的5种鸟类。另外, 红外相机还监测到较多的家畜活动(RAI = 11.14)和人为活动(RAI = 12.90), 保护区管理部门仍需采取相应管理措施, 进一步提高周边居民的保护意识, 促进保护区与社区的协调发展。  相似文献   
938.
大小兴安岭可培养细菌的资源多样性   总被引:2,自引:0,他引:2  
刘君  王宁  崔岱宗  卢磊  赵敏 《生物多样性》2019,27(8):903-11
细菌作为微生物中的重要组成部分, 在有机质的形成与分解、维持生态系统平衡、促进动植物发育等多方面都有着重要作用。2014-2017年, 我们采用常见培养基分离纯培养法及16S rRNA基因序列分析方法对大小兴安岭地区土壤可培养细菌的群落结构和多样性进行了调查研究。结果表明: 从大小兴安岭地区的17个自然保护区内不同生境的土壤中分离获得3,180个菌株, 隶属于24属120种。其中, 芽孢杆菌属(Bacillus)的种数和株数最多, 分别为38种和2,419株, 是大小兴安岭地区可培养细菌的绝对优势类群(占总株数的76.1%); 其次是短杆菌属(Brevibacterium)(13.0%)。大兴安岭地区的物种数、Simpson多样性指数和Shannon-Wiener指数高于小兴安岭地区。优势类群芽孢杆菌属的枯草芽孢杆菌(B. subtilis)、苏云金芽孢杆菌(B. thuringiensis)、巨大芽孢杆菌(B. megaterium)等有重要的生产及科学研究价值。  相似文献   
939.
为了解橄榄[Canarium album(Loureiro)Raeuschel]花序表型性状的遗传多样性,对90份橄榄种质资源的花序性状进行观测分析。结果表明,橄榄花序的类型、支轴紧密度、着生位置和花性等表现出较丰富的多样性;从数量性状看,花序花朵数的变异系数最大,其次为支轴花朵数,变异系数最小的是花蕾直径,此外橄榄雄花花序的多样性较雌花丰富。花蕾直径与花瓣长度呈极显著正相关关系,与花序长度、花序支轴数、花序花朵数和支轴花朵数呈极显著负相关。聚类分析结果表明,橄榄种质资源的花序类型可分为3类,大部分雄花和雌花类群间差异较明显。因此,橄榄花序表型性状存在多样性和复杂性,且花序重要单一性状可能影响整体表型。  相似文献   
940.
城市动物调查对监测生物多样性研究、城市生态建设具有十分重要的意义。深圳作为新兴崛起的大城市,动物多样性受城市化干扰的程度较传统大城市少,但近年来缺乏对该地区的生物资源进行全面调查。我们于2014年4月至2015年4月,在深圳市(陆域)郊区布设了57个红外相机监测点,对深圳市鸟类和兽类多样性进行了初步调查。在相机累积工作3780个捕获日中,获得动物有效照片607张,经鉴定,可辨识的兽类共3目6科8种;鸟类共计3目9科26种。其中褐翅鸦鹃被列为国家二级保护动物,列入《国家保护的有益的或者有重要经济、科学研究价值的陆生野生名录》的鸟兽共有24种。除鼠类外,相对丰富度较高的物种有灰背鸫、野猪、橙头地鸫、乌灰鸫等。经分析发现都市内野生动物的日活动节律与自然保护区的存在一定差异。本研究为在城市深入开展野生动物资源调查研究提供了一种新的思路和手段。  相似文献   
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