基于DNA宏条形码研究四川...同域共存小型哺乳动物的食性_彭步青.pdf

2023,31(4):22474,pages 114 doi:10.17520/biods.2022474 收稿日期:2022-08-18;接受日期:2022-11-24 基金项目:国家自然科学基金青年项目(32001223)、四川省自然科学基金青年基金(2022NSFSC1711)和成都市科技项目重点研发支撑计划(2021-YF05-01552-SN)*通讯作者 Author for correspondence.E-mail: https:/www.biodiversity- 基于DNA宏条形码研究四川老君山国家级自然保护区6种同域共存小型哺乳动物的食性 彭步青,陶玲,李靖,范荣辉,陈顺德,付长坤,王琼,唐刻意*四川师范大学生命科学学院,成都 610101 摘要:揭示物种共存的发生和维持机制对于群落生态学理论的发展具有重要意义,同时也是生物多样性和保护生物学研究的热点之一。生态位分化是同域分布物种实现共存的重要原因之一。为了解同域分布的多种小型哺乳动物的共存机制,本研究采用DNA宏条形码技术对四川老君山国家级自然保护区内的6种小型哺乳动物胃内容物进行分子食性分析,解析其夏季食物组成特征,并计算和比较种间食物的多样性、生态位宽度和重叠指数。结果表明:(1)鳞翅目(相对丰度:3.76%42.33%)和双翅目(2.59%62.63%)是6种小型哺乳动物的主要动物性食物,禾本目(0.02%45.33%)和豆目(0.19%38.95%)为其主要植物性食物。6种小型哺乳动物取食主要动植物性食物的相对丰度存在种间差异。(2)黄胸鼠(Rattus tanezumi)和淡灰黑齿鼩鼱(Blarinella griselda)的属水平动物性食物显著重叠(Ojk=0.63);其余物种间的营养生态位存在一定程度重叠,但在主要食物的构成和组成比例上存在明显差异;(3)6种小型哺乳动物的动物性食物多样性存在明显种间差异,而植物性食物多样性在6种小型哺乳动物之间差异不显著,其中社鼠(Niviventer confucianus)食物多样性最高,其动植物营养生态位宽度(8.211.1)均高于其余物种。以上结果表明6种小型哺乳动物的食物组成存在一定程度重叠,但在主要食物上出现分离,它们可能通过对主要食物摄食种类和比例的分化来减少竞争,实现长期共存。本研究为揭示四川老君山地区多种小型哺乳动物物种多样性的维持机制提供理论依据,也为该地区鼠形动物的生态管理提供参考。考虑到本研究在样本量和时间尺度上的局限性,未来基于营养生态位对多种小型哺乳动物进行同域共存机制研究时建议适当增加取样的时空跨度,更多的样本量能更好地反映种间关系。关键词:同域共存;食物组成;DNA宏条形码;营养生态位 彭步青,陶玲,李靖,范荣辉,陈顺德,付长坤,王琼,唐刻意(2023)基于DNA宏条形码研究四川老君山国家级自然保护区6种同域共存小型哺乳动物的食性.生物多样性,31,22474.doi:10.17520/biods.2022474.Peng BQ,Tao L,Li J,Fan RH,Chen SD,Fu CK,Wang Q,Tang KY(2023)DNA metabarcoding dietary analysis of six sympatric small mammals at the Laojunshan National Nature Reserve,Sichuan Province.Biodiversity Science,31,22474.doi:10.17520/biods.2022474.DNA metabarcoding dietary analysis of six sympatric small mammals at the Laojunshan National Nature Reserve,Sichuan Province Buqing Peng,Ling Tao,Jing Li,Ronghui Fan,Shunde Chen,Changkun Fu,Qiong Wang,Keyi Tang*College of Life Sciences,Sichuan Normal University,Chengdu 610101 ABSTRACT Aim:Revealing the mechanisms that determine species coexistence is of great importance for the development of community ecology theoretical concepts/which is one of the hot spot for biodiversity and conservation biology research.Niche separation is an important reason for the coexistence of sympatric species.Methods:To determine the dietary composition of six sympatric small mammals at the Laojunshan Nature Reserve,Sichuan,the animal samples were trapped and the luminal stomach contents were collected.We used two DNA 研究报告 彭步青等:基于DNA宏条形码研究四川老君山国家级自然保护区6种同域共存小型哺乳动物的食性 2023年|31卷|4期|22474|第2页 metabarcoding assays(chloroplast RbcL and mitochondrial COI region sequences)to better understand their dietary diversity,niche breadth and overlap.Results:(1)Lepidoptera(relative abundance:3.76%42.33%)and Diptera(2.59%62.63%)were the prey items identified,while Poales(0.02%45.33%)and Fabales(0.19%38.95%)were the taxa that constituted the majority of plant-derived foods.In addition to this,inter-specific differences in relative abundance of these main food items were observed.(2)We found that there was a significant trophic overlap(Ojk=0.63)of animal derived diet between Rattus tanezumi and Blarinella griselda.A certain degree of food niche overlap was found between the other sampled species,yet there were still significant differences in the composition and proportion of predominant food items.(3)A certain inter-specific difference in diversity of animal derived food between the six small mammals was detected,while almost no differences in diversity of plant derived foods were found between the six small mammals.Niviventer confucianus had the highest dietary diversity,with higher niches breadth(8.211.1)of both plant-and animal-derived diets than those of the other five species.Conclusion:These results suggest that,although the dietary overlap is observed in six small mammals,they can reduce foods competition and achieve long-term coexistence through separating the types and proportions of the main food items.Furthermore,this study reveals the mechanism of maintaining the diversity of various small mammal species at the Laojunshan Nature Reserve.This study also contributes to the ecological management of rodent-like animals in this area.Considering the limitations of our sample size and time scale of sampling,we believe that increasing sample size and time span can be more effective at identifying inter-specific relationship through DNA metabarcoding.Key words:sympatric co-existence;dietary composition;DNA metabarcoding;trophic niche 物种共存机制是生态学的核心课题之一,揭示物种共存的发生和维持机制对于群落生态学理论发展具有重要意义,也是生物多样性研究的热点之一。生态学家提出了多种揭示共存机制的理论和假说,其中包括资源比例假说(Huisman&Weissing,1999)、中度干扰假说(Sommer,1999)和生态位分化理论(Grinnell,1917;Udvardy,1959)。目前,针对野生动物同域共存的研究大多集中在鸟类(De Le n et al,2014;Hou et al,2021)、灵长类(Porter,2001;王丞等,2020)、食草动物(Liu et al,2007;Kartzinel et al,2015)等大中型动物,而对物种数量多、分布范围广的小型哺乳动物同域共存机制研究较为匮乏。生存需求相似的物种往往伴随着生态位的分化(Hardin,1960),竞争的结果将导致食物、栖息地和时间等资源的分化,进而促进生境内多物种共存。国内外学者围绕生态位分化理论的研究主要从时间生态位(Rutrough et al,2019)、空间生态位(杨春文,2008)和营养生态位(Cooke&Crowley,2018)等方面展开。其中,食性分析是营养生态位研究的重要组成部分,是动物根据自身营养需求对生境适应的结果(Marshal et al,2008),营养生态位即动物对食物资源的利用情况。食性分析是一项重要的基础研究内容(Cooke&Crowley,2018),可以直观展现动物的营养需求特征,反映出动物的生