【作者】 王利清；

【导师】 武晓东；

【作者基本信息】 内蒙古农业大学 ， 草业科学， 2009， 博士

【摘要】 在阿拉善典型荒漠地区,2002～2007年选择了4种不同干扰方式的样地,分别为开垦区、轮牧区、过牧区和禁牧区,分别采用标志重捕法和铗日法调查。为了揭示啮齿动物群落在脆弱的荒漠生态系统中对于不同干扰方式的反应特征,首先对不同干扰方式下啮齿动物群落密度、单位面积生物量、物种数、优势种群数量和生物量的年度变动特征进行分析对比,同时对不同年度和季节群落的数量和生物量在不同干扰区的分配进行了分析;其次分析了数量多样性指数、均匀性指数、丰富度指数、优势度指数、生物量均匀性指数的年度特征;最后从数量和生物量的角度综合分析了物种的敏感性特征及其与植被因子的相关性。结果表明:(1)群落数量年度变化过牧区较突出,轮牧区与过牧区的年间变化趋势相反,并与禁牧区有明显的差别;季节变化轮牧区和过牧区较相似,且与禁牧区有明显差异,开垦区没有统一的规律性。群落生物量过牧区年度和季节变化与数量变化趋势同,且较突出;开垦区年度变化主要由数量变化来决定,季节变化受不同种间个体生物量和种内个体生物量大小的影响,不完全由数量季节变化决定;轮牧区、禁牧区年度和季节变化均与数量变化趋势不一致。(2)6年中啮齿动物群落物种数轮牧区、过牧区较多,各干扰区群落单位面积生物量变动趋势均和密度一致。不同干扰方式下啮齿动物群落组成种数量和生物量的年度变化不同,啮齿动物群落对于人为不同干扰方式的敏感性反应特征是优势鼠种的反应不同。对不同干扰方式反应敏感的优势物种同样对群落数量消长起至关重要的作用,并影响着不同干扰群落数量和生物量的格局。荒漠啮齿动物群落组成的优势鼠种的种类变化是对于人为不同干扰方式敏感性反应的机制,优势鼠种的出现和消失可看作是群落对不同干扰的指示,即长爪沙鼠的出现和三趾跳鼠的消失是对开垦干扰方式反应敏感的指示;三趾跳鼠的出现及其数量增长是对过牧干扰反应敏感的指示。优势鼠种生物量对于人为不同干扰方式的敏感性反应特征是基于优势鼠种数量的基础上,并与不同优势种种间个体生物量的大小有关。(3)6年中不同干扰方式下啮齿动物群落Shannon-Weiner多样性指数、Simpson多样性指数、Margalef丰富度指数轮牧区、过牧区较开垦区高,Simpson优势度指数则开垦区大于轮牧区、过牧区、禁牧区。(4)数量敏感物种开垦区出现喜湿物种(黑线仓鼠),轮牧区喜湿物种(草原黄鼠)和喜旱物种(三趾跳鼠、小毛足鼠)均出现;禁牧区数量和生物量敏感物种相同,均包括五趾跳鼠、子午沙鼠;过牧区数量敏感物种较少,生物量敏感物种较多,但均包括五趾跳鼠、三趾跳鼠、草原黄鼠。子午沙鼠在不同干扰区(除过牧区外)均是数量较高、生物量较大的敏感物种。(5)轮牧区、过牧区喜旱物种与植物群落的灌木和草本有显著相关关系;开垦区(草原黄鼠和黑线仓鼠)和禁牧区(黑线仓鼠)均出现喜湿物种与植物群落变量显著的相关性;子午沙鼠在不同干扰生境中均有与植物群落变量显著的相关性,能够适应不同的干扰生境。更多还原

【Abstract】 The four kinds of sites under different human disturbance were selected in the typical region of the Alashan Desert of Inner Mongolia from April until October in 2002-2007 , i . e. a farmland area , a rotational-grazing area , a over-grazing area and a prohibited-grazing area. The four kinds of mark-recapture samples and of line samples were taken in different human disturbance areas. In inder to reveal feature of response of rodent community to different disturbance in desert fragile ecosystem , following study was done : Firstly , The features of density, biomass per hektare annual changed of rodent community and species number, number and biomass annual changed of dominant population of corresponding community were comparatively analysed under different disturbance. At the same time , Number and biomass distributed of rodent community were analysed on different disturbance areas. Secondly , Diversity indices , number eveness indices , richness indices , dominance indices , biomass eveness indices annual changed of rodent community were analysed under different disturbance. Finally , sensitive features of species number and biomass were synthetically analysed. Moreover , the corelation between species (number and biomass) and vegetation factors were synthetically analysed. The results showed:(1) The number and biomass of rodent community were distributed as follows on different disturbance areas in six years. Number annual changed of rodent community was more prominent on over-grazing area . Number annual changed of rodent community on rotational-grazing area was apposite to those of rodent community on over-grazing area. Number annual changed of rodent community on prohibited-grazing area was significantly different from those of rodent community on rotational-grazing area and over-grazing area. Number seasonal changed of rodent community on rotational-grazing area was similor to those of rodent community on over-grazing area . Number seasonal changed of rodent community on prohibited-grazing area was significantly different from those of rodent community on rotational-grazing area and over-grazing area. Regularity of number seasonal changed of rodent community on farmland area was out of accord. Biomass annual and seasonal changed of rodent community were the same as number annual and seasonal changed of rodent community and also more prominent on over-grazing area . Biomass annual changed of rodent community was decided by number annual changed of rodent community on farmland areas . Biomas seasonal changed of rodent community , which was influenced by difference between indivual biomass of different species and between indivual biomas of same species , was not entirely decided by number seasonal changed of rodent community . Biomass annual and seasonal changed of rodent community were both out of accord with number annual and seasonal changed of rodent community on rotational-grazing area and prohibited-grazing area .(2) The species number was more on rotational-grazing area and over-grazing area.. The fluctuation tendency of biomass of rodent community per hektare were all in accord with those of density(capture rate per 100 trap nights)on different disturbance areas in 6 years . The trends of annual number and biomass of component species in the rodent communities were different under different disturbance. Dominant species in rodent community showed different response under different disturbance , which was the characters of sensitive response. The dominant species of sensitivity to different human disturbance also made a key important role and influenced patterns of number and biomass in rodent community under different disturbance. The above analysis account for dominant species number in rodent community was sensitive mechanism under different human disturbance in the typical region of the Alashan Desert. The appearance and disappearance of dominant species was regarded as an indication of rodent community under different human disturbance . The results from two methods ( line sites and mark-recapture samples ) both showed : the appearance of Meriones unguiculatus and disappearance of Dipus sagitta were regarded as indication of rodent community on the farmland area ; the appearance of Dipus sagitta and rising of its number were regarded as indication of rodent community on the over-grazing area . Sensitive response of dominant species biomass was based on its number in rodent community and was correlated with size of biomass between dominant species.(3) Shannon-Weiner diversity indices , Simpson diversity indices and Margalef richness indices of rodent community on farmland area were more than those on rotational-grazing area , over-grazing area and prohibited-grazing area under different disturbance in six years .(4) The species of sensitivity to number were different and significantly varied as follows: hydrophilic species(Cricetulus barabansis) on the farmland area , hydrophilic species(Citellus dauricus) and xerophilic species(Dipus sagitta , Phodopus roborovskii) on the rotational-grazing area . The species of sensitivity to number were the same as the species of sensitivity to biomass on the prohibited-grazing area , which both included Allactaga sibirica and Meriones meridianus. The number of species of sensitivity to number were less , whereas the number of species of sensitivity to biomass were more on the over-grazing area . The species of Mutual sensitivity to number and biomass were Allactaga sibirica , Dipus sagitta , Citellus dauricus on the over-grazing area . The species of sensitivity to number and biomass both included Meriones meridianus , and the population number of Meriones meridianus was higher , also the population biomass of Meriones meridianus was larger on different disturbance areas in spite of on the over-grazing area .(5) Xerophilic species were significantly correlated with shrub and herbage on the rotational-grazing area and over-grazing area . Hydrophilic species were significantly correlated with variables of vegetation community on the farmland area(Citellus dauricus, Cricetulus barabansis) and prohibited-grazing area(Cricetulus barabansis). Meriones meridianus was significantly correlated with variables of vegetation community and was regarded as a eurytopic species in different disturbance habitats .更多还原