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  

DNA metabarcoding dietary analysis of six sympatric small mammals at the Laojunshan National Nature Reserve,Sichuan Province

作　　者：彭步青 陶玲 李靖 范荣辉 陈顺德[1] 付长坤[1] 王琼[1] 唐刻意 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)

机构地区：[1]四川师范大学生命科学学院,成都610101

出　　处：《生物多样性》2023年第4期72-85,共14页Biodiversity Science

基　　金：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);成都市科技项目重点研发支撑计划(2021-YF05-01552-SN)。

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(O_(jk)=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α多样性存在明显种间差异,而植物性食物α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(8.2–11.1)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。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 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(O_(jk)=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 inαdiversity of animal derived food between the six small mammals was detected,while almost no differences inαdiversity of plant derived foods were found between the six small mammals.Niviventer confucianus had the highest dietary diversity,with higher niches breadth(8.2–11.1)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 diversit

关 键 词：同域共存 食物组成 DNA宏条形码 营养生态位 

分 类 号：Q958.1[生物学—动物学]