| 摘要: |
| 【目的】探究贺兰山冲积扇荒漠草地地表甲虫多样性及其群落空间异质性，以及环境因子对地表甲虫群落空间分布的影响，为研究冲积扇生境地表甲虫群落演替和维持机制奠定基础。【方法】以贺兰山东麓插旗口冲积扇荒漠草地为研究区域，沿海拔梯度从冲积扇顶端到冲积扇边缘依次设置CQK1、CQK2和CQK3共3个样地，采用巴氏罐法诱捕地表甲虫，并对其进行种类鉴定及多样性分析；基于地统计学方法分析200 m×200 m空间尺度上地表甲虫的空间变异，并采用冗余分析（redundancy analysis，RDA）研究环境因子对地表甲虫群落空间分布的影响。【结果】2021年5-10月从贺兰山冲积扇荒漠草地共采集地表甲虫5 768头，隶属于11科53属75种。在扇面尺度上，步甲科和拟步甲科是地表甲虫群落的优势科，步甲科多样性以CQK1样地最大，拟步甲科多样性以CQK2样地最大；直角通缘步甲和克小鳖甲是优势种，但不同样地的优势种存在差异，CQK1样地的优势种为克小鳖甲，CQK2样地的优势种为直角通缘步甲和克小鳖甲，CQK3样地的优势种为直角通缘步甲和平坦东鳖甲。地表甲虫空间分布呈现以结构因素为主导的空间异质性，地表甲虫优势科群落空间格局呈现明显梯度分布特点，CQK1样地物种活动密度高于CQK2和CQK3样地，但CQK2样地斑块复杂程度最高，CQK1与CQK3样地物种活动密度的空间分布格局大致相反。RDA分析结果显示，在扇面景观尺度上，海拔、植被盖度和砾石覆盖度是影响地表甲虫群落物种分布的最主要环境因子，其中海拔的贡献率最高，达到55.44%。不同样地间影响地表甲虫群落物种分布的环境因子存在差异，其中CQK1样地中地形湿度指数、剖面曲率、植物多样性和砾石密度是影响地表甲虫物种分布的显著环境因子（P<0.05），CQK2样地中植被盖度、坡向和砾石覆盖度是影响地表甲虫物种分布的显著环境因子（P<0.05），CQK3样地中砾石密度、剖面曲率、坡向、平面曲率和地形湿度指数是影响地表甲虫物种分布的显著环境因子（P<0.05）。【结论】地表甲虫优势科群落多样性及优势种在不同样地间存在差异，结构性因素单一调控地表甲虫群落的空间异质性。影响200 m×200 m空间尺度不同样地物种分布的环境因子存在差异，海拔是扇面景观尺度上影响地表甲虫分布的主导因子。 |
| 关键词: 地表甲虫 空间异质性 环境因子 荒漠草地 冲积扇 |
| DOI：10.13207/j.cnki.jnwafu.2025.10.015 |
| 分类号: |
| 基金项目:国家自然科学基金项目(32360140)；贺兰山昆虫科学考察项目(D6400000141009056_3) |
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| Spatial distribution of ground-dwelling beetles and its influencing factors in alluvial fan desert grassland |
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YANG Wenbin1, WANG Yuan1, ZHU Yachao2,3, WANG Min1, YUAN Peng1, LIANG Yongliang2,3, YANG Guijun1,3
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1.College of Life Sciences,Ningxia University,Yinchuan，Ningxia 750021,China;2.Ningxia Helan Mountains National Nature Reserve Administration,Yinchuan，Ningxia 750021,China;3.Observation and Research Station of Helan Mountain Forest Ecosystem of Ningxia Hui Autonomous Region,Yinchuan，Ningxia 750021,China
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| Abstract: |
| 【Objective】In this study,the diversity and spatial heterogeneity of ground-dwelling beetle communities in the alluvial fan desert grassland of Helan Mountains,as well as the effects of environmental factors on the spatial distribution of ground dwelling beetle communities were explored,laying a foundation for the study of the succession and maintenance mechanism of ground-dwelling beetle communities in alluvial fan habitats.【Method】This study focused on the Chaqikou alluvial fan desert grassland located at the eastern foothills of Helan Mountains,employed the Pitfall trap method to trap the ground-dwelling beetles for species identification and diversity assessment of ground-dwelling beetle communities in three sample plots set along an elevation gradient:CQK1,CQK2,and CQK3.Geostatistical methods were used to analyze the spatial variation of ground-dwelling beetles across a 200 m×200 m scale.And redundancy analysis method was used to examine the influence of environmental factors on the spatial distribution of these ground-dwelling beetle communities. 【Result】A total of 5 768 ground-dwelling beetles were collected from the alluvial fan desert grassland of Helan Mountain from May to October of 2021,belonging to 75 species,53 genus and 11 families.At the fan landscape scale,Carabidae and Tenebrionidae were the dominant families in the ground-dwelling beetle communities.The diversity of the Carabidae community was the largest in CQK1,and the diversity of the Tenebrionidae community was the largest in CQK2.Pterostichus gebleri and Microdera kraatzi were the dominant species.However,there were differences in the dominant species in different plots,with CQK1 being Microdera kraatzi,CQK2 being Pterostichus gebleri and Microdera kraatzi,and CQK3 being Pterostichus gebleri and Anatolica planata.The spatial distribution of ground-dwelling beetles exhibited spatial heterogeneity,which was primarily influenced by structural factors.Kriging interpolation revealed a distinct gradient distribution in the spatial pattern of the dominant family communities of ground-dwelling beetles.The species activity density of CQK1 was higher than that of CQK2 and CQK3,but the complexity of CQK2 was the highest,and the spatial distribution pattern of species activity density of CQK1 and CQK3 was roughly opposite.RDA analysis showed that elevation,vegetation coverage and gravel coverage were the most important environmental factors affecting the species distribution of ground-dwelling beetle communities at the sector landscape scale,and altitude contributed the highest rate of 55.44%.The factors influencing the species distribution of ground-dwelling beetle communities were different among different sample plots.The topographic wetness index,profile curvature,plant diversity and gravel density were the significant environmental factors affecting distribution of ground-dwelling beetle species in CQK1 (P<0.05),vegetation coverage,slope aspect and gravel coverage were significant environmental factors affecting the distribution of ground-dwelling beetle species in CQK2 (P<0.05),and gravel density,profile curvature,aspect,plane curvature and topographic wetness index were significant environmental factors affecting the distribution of ground-dwelling beetle species in CQK3 (P<0.05).【Conclusion】There were differences in the community diversity of the dominant family and dominant species of ground-dwelling beetles,and the structural factors were the main factors regulating the spatial heterogeneity of ground-dwelling beetle communities.There were differences in the factors affecting the distribution of species in different places at the 200 m×200 m scales,and elevation was the dominant factor affecting the distribution of ground-dwelling beetles at the fan landscape scale. |
| Key words: ground-dwelling beetle spatial heterogeneity environmental factors desert grassland alluvial fan |
