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1.
刘荣堂 《生态学报》1996,16(1):65-70
通过对甘肃濒危野生动物繁育中心所在地--武威东沙窝及其周围地区植物区系调查,共获22科、84属、116种植物,以菊科、禾本科、藜科和豆科为主,占68.97%,以草本、强旱生、中温、阳性、沙生等为主要生态型。以亚洲中部成分、地中海-西亚-中亚成分,为主要地理成分。植物类群接近赛加羚羊现代分布区植物类群,而且多数类群可被羚羊采食。  相似文献   

2.
贺兰山种子植物区系的特征   总被引:11,自引:0,他引:11  
本文通过贺兰山植物区系的分析,指出该区系的主要特征是:植物种类相对丰富;地理成分复杂多样,并且有明显的过渡性;区系内部的地区性差异很大;除少数为古老类群外,多数是发生较晚的年轻类群;整个区系显示有较大的脆弱性。目的在于探求该区系的理论规律,以及为生产实践和贺兰山自然保护区的建设等提供科学依据。  相似文献   

3.
沙棘属植物的分布格局及其成因   总被引:9,自引:2,他引:7  
本文首先从植物类群、分布地域和垂直分布角度分别论述了沙棘属植物的地理分布概况,指出沙棘属在植物区系地理上,属旧世界温带分布类型;在区系成分上,是森林─—草原过渡带的成员;横断山及其毗邻的东喜马拉雅地区,是该属植物的类群分布中心、类群分化中心和原始类群中心。并对类群分布的地理替代现象、该属植物成林的丛片性特征以及果实中植化组成分与类群分布、类群进化间的相互关系进行了论述。文章最后着重对该属植物分布区格局的形成与该属植物起源的生态地理环境、散布的时间、路线以及繁育方式之间的关系进行了分析。  相似文献   

4.
通过分析华北晚中新世保德期三个经典地点的羚羊牙齿釉质之稳定碳同位素,结合相同地点的单纯食叶者(鹿科)与食草者(三趾马)的数据,推断其食性取向。结果显示这些晚中新世生态系统中C_3植物占据主导地位,但也含有一小部分的C_4植物(可能小于30%)。高冠羚羊(Gazella dorcadoides类型)取食约20%的C_4植物,而中冠羚羊(G.paotehensis类型)与低冠羚羊(G.gaudryi类型)为纯C_3植物消费者。鹿科动物单纯取食C_3植物,而三趾马与G.dorcadoides类型的羚羊取食C_4植物的比例在统计上难以区分。碳同位素数据与G.gaud- ryi类型的食叶性以及G.dorcadoides类型以草食为主的观点相一致。参照这些类群的地理分布,当前的数据支持晚中新世黄土高原东南部处于相对于西北部更为封闭环境的观点。这种环境梯度的分布方向与模式可能是该地区东亚季风体系的早期信号。  相似文献   

5.
黄土高原地区种子植物区系特征   总被引:20,自引:1,他引:19  
黄土高原在中国植物区系分区上属于泛北极植物区 ,中国 -日本森林植物亚区的华北地区黄土高原植物亚地区 ,是东西、南北旱生、中生和水生植物交汇和聚集区域。计有种子植物 1 47科 864属 32 2 4种 ,其中裸子植物 7科 1 3属 41种 ,被子植物 1 40科 85 1属 31 83种 ,具有中国特有属32个 ,黄土高原地区特有属 4个 ,特有种 1 64个。黄土高原地区种子植物区系的基本特征为 :植物种类相对丰富 ,在全国植物区系上占有重要地位 ;植物区系起源古老 ,原始类群丰富 ;地理成分复杂多样 ,以温带成分占优势 ;与周边地区区系的联系广泛 ,是多种成分汇集和过渡的地区 ;特有性程度相对低 ,稀有濒危植物丰富  相似文献   

6.
胶州湾海岸湿地维管束植物的区系特征与保护   总被引:13,自引:1,他引:12  
胶州湾海岸湿地植被分4个主要植被型、15个主要植物群落,作为湿地植被建群种、优势种和主要伴生种的维管束植物共有35科61属75种,分盐生植物、水生植物、湿生植物和沙生植物4大生态类群。其中禾本科、黎科、蓼科等7个较大科的种子植物构成了胶州湾海岸湿地维管束植物区系的主体。从分布区类型构成看,胶州湾海岸湿地植物区系成分中世界分布属最多,达24属,占总属数的39.3%,这反映了湿地植被的隐域性特征。温带分布区成分和热带分布区成分作为区系成分的主体占总属数的52.4%。针对胶州湾海岸湿地发生的退化现象,提出了保护胶州湾海岸湿地维管束植物的初步措施。  相似文献   

7.
濒危植物厚叶木莲的群落学特征及其保护   总被引:10,自引:2,他引:8       下载免费PDF全文
根据从化三角山次生常绿阔叶林的样方调查结果,分析了中国特有植物厚叶木莲(ManglietiapachyphyllaChang)的天然分布特点,分布区的自然环境概况,群落的区系特点,群落学特征及其保护策略.厚叶木莲仅零散分布于广东从化三角山、龙门南昆山和新丰小沙罗等地海拔650-1000m的常绿阔叶林中,分布区非常狭窄.在1200m~2的样地里有维管植物132种,隶属于57科89属。Shannon-Wiener物种多样性指数为5.45,均匀度为84.39%,类似于其他类群的南亚热带常绿阔叶林,但较低于海南的热带雨林类群.本群落植物区系的分布类型是以泛热带分布和热带亚洲分布两大类为主,热带-亚热带区系植物成分在本群落中占有明显的优势,其区系特点具有从热带向亚热带过渡的性质.该群落命名为赤楠、假轮叶虎皮楠、厚叶木莲群落,可分为乔木层(2亚层)、灌木层及草本层等层次.本群落以中、小高位芽植物占优势,缺乏大高位芽、地面芽和一年生植物,叶型以中型叶为主.种群分布格局分析表明,大部分优势种呈集群分布,其中厚叶木莲呈集群分布。种群的立木结构分析表明,厚叶木莲种群已处于衰退模式,有即将在群落中消失的可能,属于濒危物种,应加以保护,对厚叶木莲及其群落的保护应立足于就地保护.  相似文献   

8.
水生植物及植物表面附着微生物在人工湿地水体净化过程中发挥着重要的作用。以北京奥林匹克公园龙形水系为研究对象,通过高通量测序技术,对其底泥、水体及3种沉水植物——苦草Vallisneria natans、狐尾藻Myriophyllum verticillatum、龙须眼子菜Potamogeton pectinatus——的根际及叶际微生物群落的结构及功能进行了研究。结果表明,微生物多样性从高到低分别为底泥样品、植物根际样品、植物叶际样品和水体样品,植物叶际微生物种类要显著高于水体中微生物种类。LEfSe分析结果显示不同生境富集不同的微生物类群,其中底泥主要富集厌氧微生物类群,水体及植物叶际主要富集好氧微生物类群,植物根际则两者兼具。功能预测结果显示植物叶际样品的反硝化标志基因丰度要高于根际样品及底泥和水体样品,且狐尾藻和龙须眼子菜叶际样品反硝化标志基因丰度要高于苦草叶际样品。本研究可以为人工湿地构建时对沉水植物及功能微生物的选择提供指导意义。  相似文献   

9.
为进一步了解武功山地区油脂植物情况,通过野外调查、标本采集鉴定并结合文献的方法,对该区的油脂植物进行统计分析。结果表明武功山地区共有野生油脂植物88科213属383种;形成以樟科、豆科、蔷薇科等为主的优势科类群,以胡椒属、卫矛属、花椒属等为主的优势属类群;生活习性以木本为主。区系地理成分复杂多样,科以热带成分为主,属以温带成分为主,种的地理成分以中国特有分布最多;在分布格局上,垂直方向海拔在400~499 m范围内最多,水平方向以安福县分布油脂植物种类最多。武功山地区含油率超过30%的油脂植物高达116种,体现出该区的油脂植物具有较大的应用开发潜力。  相似文献   

10.
刘荣堂  陈本健 《生态学报》1996,16(3):265-268
在植物区系研究的基础上,作者于1988 ̄1993年在甘肃省武威市进一步研究了赛加羚羊引种区的植物群落特征,观察了30种植物的物候期,用常规方法化验了72种植物的营养成分,从植被特征出发,综合评价其对赛加羚羊的适宜性。  相似文献   

11.
刘荣堂  陈本健 《生态学报》1996,16(3):265-268
在植物区系研究的基础上,作者于1988~1993年在甘肃省武威市进一步研究了赛加羚羊引种区的植物群落特征,观察了30种植物的物候期,用常规方法化验了72种植物的营养成分,从植被特征出发,综合评价其对赛加羚羊的适宜性。  相似文献   

12.
13.
Iu I Rozhkov 《Genetika》1983,19(3):488-497
Three different types of isoenzymes, Am1, Am2 and Am3 have been revealed by polyacrylamide gel electrophoresis (PAG) and affine PAG electrophoresis in artiodactyla. In cattle and pigs Am2 isoenzyme is monomorphic, as shown by PAG electrophoresis, and polymorphic in affine gel separation (two alloenzymes, Am2A and Am2B have been revealed). Some of sheep have no Am2 isoenzyme, which, apparently, account for the presence of minus-allele. Am2 isoenzyme was not detected in Saiga tatarica which are related to sheep. In reindeer, Am2 system is monomorphic, Am3 system is polymorphic, in reindeers, Saiga tatarica and pigs the variability of the latter system being determined by A3A, A3B alleles.  相似文献   

14.
Traditional Chinese medicine (TCM) has been practiced for thousands of years, but only within the last few decades has its use become more widespread outside of Asia. Concerns continue to be raised about the efficacy, legality, and safety of many popular complementary alternative medicines, including TCMs. Ingredients of some TCMs are known to include derivatives of endangered, trade-restricted species of plants and animals, and therefore contravene the Convention on International Trade in Endangered Species (CITES) legislation. Chromatographic studies have detected the presence of heavy metals and plant toxins within some TCMs, and there are numerous cases of adverse reactions. It is in the interests of both biodiversity conservation and public safety that techniques are developed to screen medicinals like TCMs. Targeting both the p-loop region of the plastid trnL gene and the mitochondrial 16S ribosomal RNA gene, over 49,000 amplicon sequence reads were generated from 15 TCM samples presented in the form of powders, tablets, capsules, bile flakes, and herbal teas. Here we show that second-generation, high-throughput sequencing (HTS) of DNA represents an effective means to genetically audit organic ingredients within complex TCMs. Comparison of DNA sequence data to reference databases revealed the presence of 68 different plant families and included genera, such as Ephedra and Asarum, that are potentially toxic. Similarly, animal families were identified that include genera that are classified as vulnerable, endangered, or critically endangered, including Asiatic black bear (Ursus thibetanus) and Saiga antelope (Saiga tatarica). Bovidae, Cervidae, and Bufonidae DNA were also detected in many of the TCM samples and were rarely declared on the product packaging. This study demonstrates that deep sequencing via HTS is an efficient and cost-effective way to audit highly processed TCM products and will assist in monitoring their legality and safety especially when plant reference databases become better established.  相似文献   

15.
Eighteen fossil skulls of male Saiga from Northern Eurasia and 33 recent skulls from Kalmykia and Kazakhstan have been studied. Saiga from both the Khazarian Fauna of the Volga and Mammoth Fauna of Europe and Siberia are referred to Saiga horealis Tschersky, 1876. During the Pleistocene, 5. borealis distribution extended from England in the west to Alaska in the east and is characterized by an elongated neurocranium, small frontal angle of the temporal bone from the plane of the frontal, and long nasal bones.

S. borealis was a typical representative of the “mammoth biome”; in the Pleistocene periglacial steppes and cryogenic savannahs. Two subspecies are recognized: S. borealis borealis Tschersky (Eastern Sibera and Alaska); and S.b. prisca Nehring, 1891 (Europe, Urals and Western Siberia). At the end of the Pleistocene, when the mammoth disappeared, the range of S. borealis was reduced. Today they live only in West Mongolia (S. borealis mongolica Bannikov, 1946). S. tatarica tatarica was widely distributed in the other territories of the steppe and semidesert zones of Eurasia. The arid landscapes of Transcaucasia and Kazakhstan were inhabited by Saiga with thinner legs and shorter nasal bones, such as S. tatarica binagadensis Alekperova, 1953, from the middle Pleistocene of Azerbaijan (Bynagady). Fossil skulls from the Ural River that are large, but with a short neurocranium are identified as Saiga sp. cf. S. tatarica Linnaeus, 1766.  相似文献   

16.
赛加羚羊(Saiga tatarica)属于我国一级重点保护野生动物,其原产地主要为高寒低氧地区,现存种群则主要栖息于中亚地区的荒漠及半荒漠草原上。脑红蛋白是一种存在于脊椎动物体内具有运输和储存血氧能力的球蛋白,在动物适应低氧过程中具有重要的生理功能。为了初步探究赛加羚羊对低氧环境的耐受性机制,运用免疫组织化学染色法与实时荧光定量PCR技术,对脑红蛋白及脑红蛋白基因(NGB)在赛加羚羊的心、肝、脾、肺、肾等5种主要内脏器官中的分布规律与表达情况进行了探究。免疫组织化学染色结果显示,脑红蛋白在赛加羚羊的心、肝、脾、肺、肾中均有分布,阳性表达主要分布在其心肌细胞、肝细胞、脾白髓区中的淋巴细胞、肺泡细胞以及肾小球内皮细胞。实时荧光定量PCR结果显示,脑红蛋白基因在赛加羚羊心、肝、脾、肺、肾中的表达量不同,脾的表达量最高,心的表达量次之,两者均显著高于肝、肺和肾(P < 0.05);其后依次为肝、肾、肺,其中,肝的表达量显著高于肾和肺(P < 0.05),肾和肺之间表达量差异不显著(P > 0.05),肺的表达量最低。上述研究表明,脑红蛋白在赛加羚羊的主要内脏器官中均有阳性表达,不同内脏器官中的表达量不同,这表明脑红蛋白可能参与了这些内脏器官的氧利用过程,具体机制有待进一步探讨。  相似文献   

17.
Saiga antelope (Saiga tatarica) graze extensively on livestock pasture, potentially enabling transmission of a wide range of parasitic helminths between saigas and domestic ruminants. Thirty-six of the 38 species of helminth that have been found in saigas in Kazakhstan in the past have been found also in domestic livestock. We examined 133 saigas culled for meat in autumn 1997, and found three species of cestode and 12 nematodes (nine in the abomasum), but no trematodes or lungworms. The most abundant species were Marshallagia marshalli, Marshallagia mongolica, and Nematodirus gazellae in the abomasum, Nematodirus gazellae in the small intestine, and Skrjabinema ovis in the large intestine. There was no clear relationship between intensities of abomasal nematodes and body condition. Age-intensity patterns differed between species: N. gazellae intensities were highest in saigas around 2-3 yr old, and declined in older animals, whereas the intensity of Marshallagia spp. rose asymptotically with age. Fecal egg density was directly proportional to adult worm intensity across ages for Marshallagia spp., but only in young animals for N. gazellae. There was no evidence that helminths, at the intensities observed, adversely affect saiga populations. The host range of many of the parasites found is broad, and transmission between saigas and livestock in both directions might become important to agriculture and conservation as livestock numbers recover. Simplified sampling techniques used in this study, and statistical analysis based on bootstrapping, could prove useful in other parasitologic surveys of wildlife in remote areas.  相似文献   

18.
Effective conservation requires a good understanding of factors causing variation in population growth rate. We here analyse the relationship between female age and fecundity in the saiga antelope Saiga tatarica tatarica , a critically endangered ungulate of the Eurasian steppes and semideserts, at both individual and population levels. Annual variation in age structure and twinning rates was investigated using long-term datasets, sampling a total of 3308 females in four populations over more than 40 years. Further, a new non-invasive method is presented, estimating twinning rates from both calves and placentas encountered during calving aggregation transects. At an individual level, the most parsimonious model for twinning rates included three age classes (1, 2 and ≥3 years); however, the model with only two classes (1 and ≥2 years) was competitive and particularly useful for monitoring because these two age classes can reliably be determined by direct observation in the field. Among yearlings, 77.4% were fecund and 11.7% twinned, whereas among older females 94.6% were fecund and 72.6% twinned. At a population level, annual variation in age structure (proportion ≥2 years) correlated well with annual variation in twinning rate except in the north-west Pre-Caspian population. Our results suggest that the recent poaching-driven collapse in saiga numbers has potentially resulted in reductions in fecundity, which will have an impact on population growth rate. Our results highlight the potential for monitoring of twinning rate using non-invasive calving aggregation transects as a cost-effective additional tool to population counts for monitoring the status of this critically endangered species. These monitoring methods are also potentially transferable to other ungulate species.  相似文献   

19.
Kuhn TS  Mooers AØ 《Molecular ecology》2010,19(22):4834-4836
Conservation biologists understand that linking demographic histories of species at risk with causal biotic and abiotic events should help us predict the effects of ongoing biotic and abiotic change. In parallel, researchers have started to use ancient genetic information (aDNA) to explore the demographic histories of a number of species present in the Pleistocene fossil record (see, e.g. Shapiro et al. 2004). However, aDNA studies have primarily focused on identifying long-term population trends, linked to climate variability and the role of early human activity. Population trends over more recent time, e.g. during the Holocene, have been poorly explored, partly owing to analytical limitations. In this issue, Campos et al. (2010a) highlight the potential of aDNA to investigate demographic patterns over such recent time periods for the compelling and endangered saiga antelope Saiga tatarica (Fig. 1). The time may come when past and current demography can be combined to produce a seamless record. [Figure: see text].  相似文献   

20.
Aim Long‐distance migrations of terrestrial animals, driven by needs such as food, water and escaping predators and harsh climatic conditions, are widely known phenomena. The saiga antelope (Saiga tatarica tatarica) migrates over long distances in the semi‐arid rangelands of Central Asia. Both the saiga’s range and its populations have been severely affected by socio‐political and land use changes over the last century, related to the formation and dissolution of the Soviet Union. We identified ecological drivers of saiga migration, compared four populations in terms of differences in the geographical characteristics of their ranges and the factors affecting habitat selection within the seasonal ranges. Location Kazakhstan and pre‐Caspian Russia. Methods Using 40 years of direct observations, we tested for differences between the four saiga populations’ ranges in terms of precipitation, seasonal productivity and topographical variables using discriminant analyses. We tested hypotheses concerning the drivers of migration to their seasonal ranges and assessed the impact of peak and average values and the predictability of drivers of habitat use within the seasonal ranges using logistic regressions. Results Three of the four populations migrate in a similar way, following a latitudinal gradient driven by seasonal changes in productivity, which is closely related to broad‐scale differences in precipitation. Intermediate productivity and its low interannual variability determine habitat selection within the seasonal ranges of all the populations. Main conclusions Migration of all four populations is driven by productivity and precipitation. The migrations in Kazakhstan are still intact despite major recent disruption to the populations, whereas their status in the pre‐Caspian region is unknown. All four populations are under severe threat from habitat loss, poaching, lack of protection and gaps in ecological knowledge. A better understanding of the drivers of saiga migration at multiple scales is a key step towards addressing these threats.  相似文献   

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