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1.
有蹄类食性研究方法及研究进展   总被引:19,自引:0,他引:19  
郑荣泉  鲍毅新 《生态学报》2004,24(7):1532-1539
国内外有蹄类食性的研究方法主要有直接观察法、利用法、胃分析法和粪便显微分析法。近年来 ,粪样 DNA分析技术逐渐运用到对动物食性的判定上 ,其中粪便显微分析法是近 2 0年来国内研究有蹄类食性的最主要方法。对这些方法的优势和局限性进行了评价 ,并简述了国内外有蹄类食性研究进展和发展趋势  相似文献   

2.
羊年说羊     
羊是人们最熟悉的动物。我们通常谈到的羊是家养的绵羊与山羊。除了这些,在自然界还存在许多野生的羊如山羊与羚羊。山羊与羚羊都是有蹄类动物。有蹄类动物的祖先6000万年前才出现。它们适应了地球上的各种各样生态环境,形成了众多的种类。有蹄类动物都是草食动物,按照其蹄的数目是奇数还是偶数,分为奇蹄目和偶蹄目。植物体的主要成分之一是纤  相似文献   

3.
青藏高原是地球上一个独特的自然地理单元, 具有丰富的生境类型和生物种类, 是生物多样性与全球环境变化领域的热点研究区域。青藏高原发育着独特的动物区系, 尤其是有蹄类动物, 如藏羚(Pantholops hodgsonii)、野牦牛(Bos mutus)、藏原羚(Procapra picticaudata)、普氏原羚(P. przewalskii)、白唇鹿(Przewalskium albirostris)等青藏高原特有动物。在本文中, 我们探讨了如下问题: 青藏高原有多少种有蹄类动物?有多少种特有有蹄类动物?其分布格局如何?生存状况如何?保护现状如何?我们首先确定了青藏高原动物地理区的地理边界。发现青藏高原有28种有蹄类, 其中10种是青藏高原特有种。青藏高原有蹄类种数占中国有蹄类的42%, 单位面积上的有蹄类物种密度比中国现生有蹄类物种平均密度高62%。特有种比例高达36%。然而, 青藏高原有蹄类物种分布不均匀, 其丰富度呈东部高西部低格局, 而高原特有有蹄类则分布于高原腹地。青藏高原有蹄类动物生存受威胁比例高, 其中71%为受威胁物种, 54%被列入濒危野生动植物种国际贸易公约(CITES)附录I或附录II。野外调查发现大额牛(Bos frontalis)已经野外灭绝, 目前仅在高黎贡山有人工养殖的群体。青藏高原有蹄类物种红色名录指数从1998-2015年呈现持续下降趋势, 全球气候变化将加剧这一趋势。青藏高原有蹄类受威胁局面仍在继续, 物种生存状况持续恶化。虽然经过40年的自然保护区建设, 但一些青藏高原有蹄类的重要种群与栖息地并没有被自然保护区和新建的三江源国家公园所覆盖。因此, 在开发青藏高原、实现人类社会经济发展目标的同时, 应尽量保存高原野生动物种群与生境, 实现青藏高原草地生态系统的可持续利用与生物多样性保护的双赢目标。  相似文献   

4.
驼鹿的圣地     
汗马蕴育着我国独特的寒温带森林湿地动物群.在众多的物种中,以大型有蹄类动物为代表的物种多样性、丰富度和独特性令人惊叹! 有蹄类是动物界的重要组成部分,亦是现存最大群的大型陆生动物,是自然界食物网的主要环节;同时,作为动物界的一部分,有蹄类对生态系统有着重要的影响.有蹄类动物中,驼鹿是鹿科动物中的体型最大者.尽管驼鹿广泛分布于欧洲和北美,但我国驼鹿种群是亚洲最南部的种群.它是国家Ⅱ级保护野生动物,别名:犴、堪达犴.驼鹿这个鹿科动物中的巨人,也是对环境变化非常敏感的物种之一.  相似文献   

5.
刘辉  姜广顺  李惠 《生态学报》2015,35(9):3076-3086
科学的种群数量调查方法的探索一直是困扰北方有蹄类动物种群资源有效管理工作的重要问题。目前,北方野生有蹄类调查所采用的方法主要有样线法、样带法、大样方法和非损伤性CMR法4种。然而,不同的调查方法基于的统计学假设和生态学原理不同,调查结果往往会出现很大差异,迫切需要对北方冬季有蹄类动物的这4 种调查方法的有效性进行评估。以驼鹿种群数量调查为例,采用样线法、样带法、大样方法和非损伤性CMR调查法,于2012年3月和2012年12月对内蒙古汗马国家级自然保护区约120 km2的区域驼鹿种群数量进行了调查和评估。 结果显示,以上4 种方法得到的驼鹿种群数量分别为:样线法168(109-227) 只,样带法237(165-309) 只,大样方法37(23-50) 只,非损伤性CMR法55(43-68) 只,表明样线法和样带法的调查结果远大于大样方法和非损伤性CMR法,并探讨了不同调查方法应用的科学性、限制性和适用性,为北方冬季有蹄类动物种群资源调查方法的选择和应用提供了科学参考。  相似文献   

6.
当今,学者已经在啮齿类和灵长类动物中建立了胚胎干细胞系,然而在有蹄类家畜中还没有获得成功。诱导重编程技术的建立为再生医学的快速发展以及农业动物繁育技术体系的革新提供了重要的技术支持,也为获得有蹄类家畜多能干细胞提供了新的思路和方法。目前,虽然在猪、牛、绵羊、山羊和马中都获得了诱导多能性干细胞(induced pluripotent stem cells,i PSCs),但是其在体外培养及细胞特性等方面与啮齿类和灵长类i PSCs还有较大差距。该文主要对有蹄类家畜i PSCs研究的现状、存在的问题及解决思路进行系统综述,为进一步推进有蹄类家畜i PSCs的研究提供理论支持。  相似文献   

7.
驼鹿的圣地     
汗马蕴育着我国独特的寒温带森林湿地动物群。在众多的物种中,以大型有蹄类动物为代表的物种多样性、丰富度和独特性令人惊叹!有蹄类是动物界的重要组成部分,亦是现存最大群  相似文献   

8.
三江源国家公园成立后,人们需要了解该区域关键有蹄类物种如藏野驴(Equus kiang)、藏原羚(Procaprapicticaudata)和藏羚羊(Pantholops hodgsonii)等物种的分布和数量,以便制定相应的保护规划.我们于2014~2017年夏季在三江源53.8×10~4km~2的范围内进行了样线调查,考察行程总计14597.8 km,记录到藏野驴3711头,藏原羚1187只,藏羚羊423只.为了准确估计有蹄类的数量,我们用随机森林模型量化了物种分布与22个环境变量的关系,预测了三大有蹄类在整个区域的分布和数量,并通过样线调查的数据进行校正,得到藏野驴、藏原羚和藏羚羊在三江源研究区域的总数分别为44240头、13162只和2390只.四年来三大有蹄类数量稳定.我们应用距离抽样的探测函数、随机森林模型中环境变量对物种数量的解释程度以及调查结果和模型结果的匹配程度进行不确定性分析,计算了动物估计数量的置信区间.我们建立了新的动物数量估计方法,适合于动物分布与环境变量关系密切并有样线调查结果的情况.  相似文献   

9.
虽然调查草原有蹄类有许多方法,但考察中必须对有关方法进行修正,本文描述了笔者在青海省野牛沟调查3种草原有蹄类动物时,为满足样线法的假设前提而采取的具体措施。笔者建议,无论采用何种统计方法,都应当认真研究该方法的假设前提,并在研究报告中说明为满足假设而作出的细节安排。  相似文献   

10.
郑生武  左青云 《兽类学报》1989,9(2):130-136
1987年8—10月,作者在甘肃省肃北蒙古族自治县盐池湾白唇鹿自然保护区研究了有蹄类动物栖息地类型、群落结构和数量等级。  相似文献   

11.
Trivers and Willard's suggestion that natural selection favors maternal control of offspring sex ratio in relation to maternal condition has been much debated. The theoretical plausibility of the idea, under some conditions, is firmly established, and there is strong empirical support for conditional sex allocation in some taxa. However, the extent to which this hypothesis can be applied to mammals, particularly ungulates, has been more controversial. We used meta-analysis to review published studies of the Trivers-Willard hypothesis within ungulates and to assess the overall level of empirical support for the hypothesis. Overall, data from 37 studies of 18 species suggested a weak but significant positive correlation between maternal condition and sex ratio (r=+0.09). However, average effect size differed markedly between different categories of studies. Studies using measures of maternal condition that were taken preconception and on the basis of behavioral dominance provided strong evidence for a relationship between maternal condition and the sex ratio (r=+0.17-0.25). In contrast, studies that used morphological or physiological measures of condition that were measured postconception provided little or no evidence for a relationship between maternal condition and sex ratio (r=+0.05-0.06). There are several reasons to suggest that data collected postconception and relying on morphological measures of condition are less likely to capture variables that cause selection for biased sex allocation. In addition, we found that the relationship between sex ratio and maternal condition depended on life-history characteristics; relationships were stronger when sexual size dimorphism was more male biased and when gestation periods were longer. Overall, our analyses suggest that data from ungulates are consistent with the Trivers-Willard hypothesis but only when appropriate measures are used.  相似文献   

12.
Subungulate hyraces are similar to the condition assumed to have characterized primitive ungulates and subungulates by virtue of their small body size, relatively unspecialized cranial and postcranial anatomy, and primitive type of lophodont dentition. The muscles of mastication of Procavia habessinica and Heterohyrax brucei are here compared with those of other mammals, both with ungulates, as an example of more specialized mammals, and with opossums, as an example of more generalized mammals, to determine aspects of hyrax myology that represent the retention of a condition primitive for herbivorous mammals. The masticatory muscles of hyraces retain the primitive ungulate/subungulate condition in the large, complexly subdivided temporalis, and in the enlarged, pinnated, bilayered medial pterygoid. The medial pterygoid originates from the pterygoid hamulus, a condition that may also be primitive for this assemblage. The large complex superficial masseter is derived compared with the condition in ruminant artiodactyls, but may represent the condition primitive for perissodactyls. The architectural modifications of this muscle in hyraces may represent adaptations to allow a wide gape threat display. Hyraces possess a posterior belly of the digastric alone, paralleling the condition in some perissodactyls. They possess a large and complexly subdivided styloglossus, which may be a shared derived character of subungulates. Hyraces are unique among ungulates and subungulates in the extreme reduction of the anterior hyoid cornua, and may be unique among mammals in the development of paired lingual processes from the ceratohyal ossifications.  相似文献   

13.
Body condition is a useful measure of the nutritional status and performance in ungulates. The most widely used indicators of body condition are based on fat reserves, mainly those surrounding the kidneys. To estimate the body condition in large herbivores, researchers often collect and pool the data from both kidneys and their perirenal fat in order to compensate for potential differences between the body condition indicators obtained from the left and right kidneys. Since these differences do not seem to be properly established in wildlife, we checked for the potential differences between the body condition indicators, derived from both kidneys, in wild ungulates. In the present study, we used red deer Cervus elaphus, both under experimental and field conditions, as a model to analyse the patterns of response of the body condition indicators, calculated from left and right kidneys, to supplementary feeding, sex, age class and season. By considering two analytical approaches – kidney fat index and fat weight (including kidney weight as a covariate) – we consistently obtained similar statistical results and the same ecological interpretations by using left, right and average indicators for all the factors tested. In the experimental study, supplementary feeding had a significant effect on all the body condition indicators of red deer hinds. Under field circumstances, the condition indicators were statistically higher in females than in males and they increased with age. Sex related differences were significant in the winter. Taking into account our results, we hypothesize that information from only one kidney will be enough to assess the body condition in red deer and probably in other wild ungulates. However, a standardized sample (i.e. always using the same kidney and associated fat) should be used, while a better understanding regarding possible asymmetries in the amount of the energy reserves on each side of the animals’ bodies has not been reached. Our study has clear implications concerning wildlife monitoring since it represents a considerable reduction of time and effort, both in the field (collecting the samples) and in the laboratory (processing and weighing the samples) when evaluating the body condition of individuals and populations.  相似文献   

14.
Ungulates inhabiting high latitudes schedule the timing of conceptions so that offspring are born during the most favourable nutritional conditions for reproductive success. The optimal period for births is less reliably predictable in tropical and subtropical savanna environments where plant growth is governed by rainfall, suggesting that reproductive phenology could be influenced more proximately by resources affecting the body condition of females around the time of conceptions. To assess how these controls operate, we compared the timing of births and conceptions among tropical and subtropical savanna ungulates with the patterns shown by ungulates in northern temperate or subarctic latitudes. The association between the timing of births and the onset of plant growth early in the growing season is less consistent among tropical savanna ungulates than among ungulates inhabiting northern temperate environments, and apparently subject to other influences affecting vegetation phenology. Nevertheless, birth peaks seem to coincide with the time of the year when forage quality is expected to be best for offspring survival and growth for most tropical or subtropical ungulates with gestation periods shorter than a year. When gestation time exceeds one year, proximal effects of nutritional conditions around the time of conceptions apparently become overriding and birth synchrony with early season plant growth is no longer effective. Proximate nutritional influences on conceptions may also govern the somewhat diffuse spread of births shown by ungulate populations in equatorial latitudes where photoperiod cues controlling oestrus and mating cannot be used to schedule the later timing of births.  相似文献   

15.
Ungulate abundance has increased dramatically worldwide, having strong impacts on ecosystem functioning. High ungulate densities can reduce the abundance, diversity and/or body condition of small mammals, which has been attributed to reductions in cover shelter and food availability by ungulates. The densities of wild ungulates have increased recently in high-diversity Mediterranean oak ecosystems, where acorn-dispersing small rodents are keystone species. We analysed experimentally ungulate effects on seed-dispersing rodents in two types of oak woodland: a forest with dense shrub layer and in dehesas lacking shrubs. Ungulates had no significant effects on vegetation structure or rodent body mass, but they reduced dramatically rodent abundance in the lacking-shrub dehesas. In the forest, ungulates modified the spatial distribution and space use of rodents, which were more concentrated under shrubs in the presence than in the absence of ungulates. Our results point to the importance of shrubs in mediating ungulate–rodent interactions in Mediterranean areas, suggesting that shrubs serve as shelter for rodents against ungulate physical disturbances such as soil compaction, trampling or rooting. Holm oak seedling density was reduced by ungulates in dehesa plots, but not in forests. Acorn consumption by ungulates may reduce oak recruitment to a great extent. Additionally, we suggest that ungulates may have a negative effect on oak regeneration processes by reducing the abundance of acorn-dispersing rodents. Given that shrubs seem to mediate ungulate effects on acorn dispersers, controlled shrub encroachment could be an effective alternative to ungulate population control or ungulate exclusion for the sustainability of the high-diversity Mediterranean oak ecosystems.  相似文献   

16.
Faecal pellet counts have been widely used to monitor the abundances of introduced ungulates in New Zealand, but ground-based sampling cannot be conducted safely in the steep non-forest habitats that are common in New Zealand's Southern Alps. Helicopter counts may be an effective technique for monitoring ungulates in steep non-forest habitat. We evaluated the relationship between faecal pellet and helicopter counts of ungulates (primarily feral goat Capra hircus) at 12 non-forest sites in the Southern Alps. Within each site we counted the numbers of ungulates from a helicopter on three occasions and the number of intact faecal pellets along 30 transects. Mean observed densities of feral goats derived from helicopter counts ranged from 0.0 to 20.2 km?2. There was a positive curvilinear (concave down) relationship between faecal pellet and helicopter counts. Compared with faecal pellet counts, helicopter counts were cheaper, could identify ungulate species and provided estimates of absolute density. Helicopter counts are a cost-effective method for monitoring ungulates in the steep non-forest habitats of New Zealand's Southern Alps.  相似文献   

17.
Disturbances like biological invasions and fire may affect in unexpected ways plant-animal interactions. In northwestern Patagonia, introduced ungulates (cattle, horses and deers) are widespread and very common occupying more than 50% of forests and shrublands, widely affecting these habitats. In addition, fire play a major role in creating landscape patterns in this region. We evaluated whether fire modify the impacts of introduced ungulates on plant-animal interactions. In a mature forest (unburnt) and in an early post-fire area (burnt) we used structural equation modeling (SEM) to analyzed the impacts of introduced ungulates on insect herbivory, pollination and pre-dispersal seed predation on Berberis darwinii, one of the most common understory shrub of temperate forests. We found that the effects of cattle on pollination and fruit set depended on the habitat condition (i.e. unburnt or burnt). Introduced ungulates in unburnt forest decreased fruit set through a reduction on pollinator visits. Conversely, introduced ungulates in burnt forest increased pollinator visits and flower production without affecting fruit set. On the other hand, damage patterns (herbivory and fruit/seed predation) were unaffected by cattle in both forests types. Either, low browsing pressure or induction of plant defences may explain our results. This study illustrates how modifications on biotic and abiotic conditions produced by fire may affect in complex ways the effect of introduced ungulates on plant-animal interactions.  相似文献   

18.
Integrative studies of plant–animal interactions that incorporate the multiple effects of interactions are important for discerning the importance of each factor within the population dynamics of a plant species. The low regeneration capacity of many Acacia species in arid savannas is a consequence of a combination of reduction in seed dispersal and high seed predation. Here we studied how ungulates (acting as both seed dispersers and herbivores) and bruchid beetles (post-dispersal seed predators) modulate the population dynamics of A. raddiana, a keystone species in the Middle East. We developed two simulation models of plant demography: the first included seed ingestion by ungulates and seed predation by bruchids, whereas the second model additionally incorporated herbivory by ungulates. We also included the interacting effects of seed removal and body mass, because larger ungulates destroy proportionally fewer seeds and enhance seed germination. Simulations showed that the negative effect of seed predation on acacia population size was compensated for by the positive effect of seed ingestion at 50 and 30% seed removal under scenarios with and without herbivory, respectively. Smaller ungulates (e.g., <35 kg) must necessarily remove tenfold more seeds than larger ungulates (e.g., >250 kg) to compensate for the negative effect of seed predation. Seedling proportion increased with seed removal in the model with herbivory. Managing and restoring acacia seed dispersers is key to conserving acacia populations, because low-to-medium seed removal could quickly restore their regeneration capacity.  相似文献   

19.
森林放牧是中国东北虎豹国家公园内影响最广泛且强度最大的人类干扰之一。研究放牧对有蹄类动物食物资源的影响,是估算当前状态下东北虎和东北豹主要猎物承载力的关键,可以为国家公园的管理提供有效的科学依据。本研究于2016年在中国东北虎豹国家公园东部的牧场和非牧场区域分层抽取50个林下样地设置围栏对照实验,于2017年生长季进行灌草层植被调查 (每个样地的围栏与对照各随机调查3个1m×1m的样方,共调查300个植物样方) ,并应用红外相机技术获取对照样地内有蹄类动物丰富度和活动情况,研究放牧对研究区灌草层植物及动物的影响。研究结果显示:在生长季内,森林放牧显著降低林下灌草层植物生物量 (减少约24%),牧场样地的嫩枝叶显著降低。除禾草外,牧场样地中其他类别植物的氮含量均显著高于非牧场样地 (平均超出非牧场样地25 %)。非牧场样地梅花鹿的相 对丰富度指数 (RAI) 显著高于牧场样地,而狍与野猪的相对丰富度指数 (RAI) 在这两类样地之间没有显著差别。研究结果表明,东北虎豹国家公园东部森林放牧,减少了有蹄类动物灌草层食物资源,降低了有蹄类动物的多度。建议停止森林放牧,恢复有蹄类动物栖息地。  相似文献   

20.
We investigated density dependence on the demographic parameters of a population of Camargue horses (Equus caballus), individually monitored and unmanaged for eight years. We also analysed the contributions of individual demographic parameters to changes in the population growth rates. The decrease in resources caused a loss of body condition. Adult male survival was not affected, but the survival of foals and adult females decreased with increasing density. Prime-aged females maintained high reproductive performance at high density, and their survival decreased. The higher survival of adult males compared with females at high density presumably results from higher investment in reproduction by mares. The high fecundity in prime-aged females, even when at high density, may result from artificial selection for high reproductive performance, which is known to have occurred in all the major domestic ungulates. Other studies suggest that feral ungulates including cattle and sheep, as these horses, respond differently from wild ungulates to increases in density, by trading adult survival for reproduction. As a consequence, populations of feral animals should oscillate more strongly than their wild counterparts, since they should be both more invasive (as they breed faster), and more sensitive to harsh environmental conditions (as the population growth rate of long-lived species is consistently more sensitive to a given proportional change in adult survival than to the same change in any other vital rate). If this principle proves to be general, it has important implications for management of populations of feral ungulates.  相似文献   

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