Study on Age and Bunch Structure of Four Stipa Species in Inner Mongolia Plateau

The age status of four Stipa L. species, S. baicalensis Roshev., S. grandis P. Smim., S. krylovii Roshev., and S. klemenzii Roshev. in Inner Mongolia plateau was analyzed using a transect sampling method. The ontogeny of Stipa species was divided into five stages: the seedling, juvenile, reproductive, presenile, and senile. Dynamics of the population age speetra were determined mainly by the appearance of new individuals and their death rate. The survival rate of the seedlings was very low while that of file adults was high. The considerable longevity of bunch life allowed the old individuals to accumulate in the population. Both S. grandis and S. krylovii had higher proportion of seedlings than others. The proportion of the juveniles and the reproductives in the population decreased from S. baicalensis community to S. klemenzii community, but the old individuals including the preseniles and the seniles showed a reverse pattern. The aging process occurred in bunch level was characterized by the fragmentation of bunch and the within-bunch- self-thinning of the tillers. The process of within-bunch-self-thinning can be described by power equation Y: aXb. Meanwhile as a response to enviroument changes especially to the fluctuation of annual precipitation and its seasonal distribution both the numbers of reproductive shoots and vegetative shoot mass within a bunch were variable.     

内蒙古锡林河流域不同生境中蝗虫种类组成的分析

本文对内蒙古锡林河流域不同生境中蝗虫种类发生的情况进行了分析。经过系统取样和大面积扫网调查,共采集到蝗虫21种,这些种类在各生境中出现的情况,与生境的复杂程度存在很大的关系。在复杂的生境中,蝗虫种类最丰富。根据锡林河流域不同生境中蝗虫种类发生的情况,经过比较分析,我们认为在该区域存在的沙带生境是典型草原的“蝗虫库”。“蝗虫库”的存在,对牧业生产构成一定的潜在威胁。经存在度分析表明,一些常见的种类,生态分布幅度宽,同时,它们又是当地的优势种害虫,为害大,是重点防治对象。     

Reconsidering the Role of Absentee Herd Owners: A View from Mongolia

Since the privatization of livestock in 1992, rates of absentee ownership of livestock have increased sharply in Mongolia. Unlike other documented instances of absentee herding in pastoral societies, absentee herd ownership has few detrimental ecological or social impacts in Mongolia. Rather, the relationship between absentee herd owners and herders may be viewed as a revitalized institution, with links to customary patterns of urban-rural exchange, emerging to meet the needs of both herders and town-dwellers during the transition from a socialist planned economy to a free market economy. Absentee herding in Mongolia differs from absentee and contract herding accounts from Africa and the Middle East in its continuing emphasis on subsistence rather than speculative investment and accumulation. Other important distinctions include: (1) absentee owners and herders are usually kin or friends; (2) herders tend their own private herds in addition to absenteeowned animals;(3)few ethnic, caste, or class differences existbetween herders and absentee herd owners; and (4) herders from all wealth strata tend absentee-owned animals. Policies to restrict or regulate absentee livestock ownership must be carefully considered in the Mongolian context, making clear distinctions between informal, mutually beneficial subsistence-driven arrangements among kin and friends, and more formal investment-driven contracts between businesses or investors and herders.     

内蒙古高原四种针茅种群年龄与株丛结构的研究

用样带法调查了内蒙古高原4种针茅(StipaL.)的年龄结构,并将其年龄划分为5个阶段:幼苗、幼龄、成年、老龄前期和老龄期。结果表明:幼苗对种群年龄结构和动态有较大的影响,针茅幼苗的存活率通常很低,而成年株丛的存活率较高,株丛的实际寿命很长,老龄株丛在种群中占有较大的比例。4种针茅中大针茅(S.grandisP.Smirn.)和克氏针茅(S.kryloviiRoshev.)的幼苗比例较高,从贝加尔针茅(S.baicalensisRoshev.)群落到小针茅(S.klemenziiRoshev.)群落种群中幼龄和成年株丛比例呈下降的趋势,而老龄株丛比例呈增加的趋势;针茅属植物在株丛水平上的动态主要表现为株丛的破碎与枝条自疏过程,以及株丛生殖枝数量和营养枝生物量的波动,幂函数模型Y=aXb可以对株丛的枝条自疏过程进行定量描述     

内蒙古科尔沁草原黑玉蚂蚁巢窝中华二索线虫及黑玉蚂蚁索幼虫的观察

内蒙科尔沁草原是牛羊胰脏阔盘吸虫病及肝脏双腔吸虫病严重的流行区。作者从双腔吸虫的昆虫宿主（第二中间宿主） 黑玉蚂蚁（Ｆｏｒｍｉｃａ ｇａｇａｔｅｓ） 腹中查获索线虫幼虫, 检到从黑玉蚂蚁腹部自动弹出的后感染期的索幼虫。与此后感染期索幼虫同形态的索幼虫在黑玉蚂蚁巢窝土壤中也找到。黑玉蚂蚁巢窝土壤中有数种索科线虫, 仅中华二索线虫（ Ａｍｐｈｉｍｅｒｍｉｓｃｈｉｎｅｎｓｉｓ） 的雌雄成虫在长细大小以及形态结构上与黑玉蚂蚁索幼虫相像, 它们是否同一种类尚待实验证实。     

基于PSR框架的内蒙古自治区土壤保持服务分区

土壤侵蚀是中国北方重要的生态问题,内蒙古自治区位于干旱半干旱地区,是中国北方典型的土壤侵蚀区。针对以往生态功能分区分析框架复杂多样、权重设定人为主观等问题,以内蒙古自治区为例,基于压力-状态-响应系统分析框架,从气候背景-土壤保持-植被条件三方面构建指标体系,运用自组织特征映射(SOFM)神经网络和GIS空间分析技术,以1280个小流域为基本单元进行土壤保持服务分区,按照分区单元的聚集度对多种方案进行优选,并依据区域共轭性原则最终将研究区划分为3个土壤保持服务区和11个土壤保持服务亚区。     

Inner structural organization of the distal humerus in Paranthropus and Homo

The taxonomic attribution of isolated hominin distal humeri has been a matter of uncertainty and disagreement notwithstanding their relative abundance in the fossil record. Four taxonomically-based morphotypes, respectively representing P. boisei, P. robustus, non-erectus early Homo and H. erectus, have been identified based on the cross-sectional outer shape variation of an assemblage of Plio-Pleistocene eastern and southern African specimens (Lague, 2015). However, the existence of possible differences between Paranthropus and Homo in the inner structural organisation at this skeletal site remains unexplored. We used noninvasive imaging techniques to tentatively characterize the endostructural organization of five early Pleistocene distal humeri from South Africa (TM 1517g, SK 24600, SKX 10924, SKX 34805) and Ethiopia (Gombore IB), which have been variably attributed to Paranthropus or Homo. While the investigated specimens reveal diverse degrees of inner preservation related to their taphonomic and diagenetic history, in all but SK 24600 from Swartkrans we could comparatively assess some geometric properties at the most distal cross-sectional level (%CA, I_x/I_y, I_max/I_min) and quantify cortical bone thickness topographic variation across the preserved shaft portions by means of a 2-3D Relative Cortical Thickness index. Whenever possible, we also provided details about the site-specific organization of the cancellous network and measured the same parameters in a comparative sample of twelve adult extant humans. For most features, our results indicate two main patterns: the first includes the specimens TM 1517g, SKX 10924 and SKX 34805, while the second endostructural morphotype sets apart the robust Homo aff. erectus Gombore IB specimen from Melka Kunture, which more closely resembles the condition displayed by our comparative human sample. Notably, marked differences in the amount and pattern of proximodistal cortical bone distribution have been detected between Gombore IB and SKX 34805 from Swartkrans. Given its discordant outer and inner signatures, we conclude that the taxonomic status of SKX 34805 deserves further investigations.     

Germination ecology of Central Asian Stipa spp: differences among species, seed provenances, and the importance of field studies

Stipa-species are wide-spread in Central Asia, but sexual reproduction in the dry steppes is rare. To facilitate conservation and restoration of these important rangelands, we studied germination characteristics of three common Mongolian Stipa-species under field- and lab conditions. Seeds of Stipa krylovii, Stipa gobica and Stipa glareosa were sown at the study site in Southern Mongolia over two consecutive years during which period tests were carried out to ascertain whether competition or herbivory are the main constraints of seedling establishment. In addition, we tested germination and seed viability in the laboratory under two different temperature regimes (20/10°C and 8/4°C), as well as the effect of cold-stratification. The lab experiments also included S. krylovii seeds originating from three climatically different provenances. None of the three Stipa-species seedlings emerged during the first 2 years of the field study. However, after an unusually intense rain event in the third year, 3% of S. krylovii, 0.6% of S. glareosa and 0.1% of S. gobica seeds germinated in the study plots. The factors ‘sowing-year’ and ‘vegetation’ significantly affected seedling emergence, whereas grazing had no effect at all. Under laboratory conditions a high percentage of viable seeds of S. gobica and S. glareosa germinated at both incubation temperatures, and cold-stratification had no effect on germination or viability. Germination of S. krylovii seeds required warmer temperatures and cold-stratification had a positive effect. Such evidence for dormancy was more pronounced in seeds from the moister, northern provenances. Germination of Stipa-species in the field is rare and only possible under exceptionally moist conditions. Conservation should thus concentrate on steppe conservation rather than on restoration. Where artificial reseeding is necessary, differences among species and also among different seed provenances should be taken into account.     

不同发育时期樟子松（Pinus sylvestris L. var. mongolica Litv.）的电阻抗参数与抗寒性的关系

采用电阻抗图谱（EIS）法和电导（EL）法对不同发育时期的樟子松（Pinus sylvestris L. var. mongolica Litv.）茎和针叶进行了抗寒性测定,试图通过比较两种方法测定抗寒性结果的相关性,找到适合冷冻处理后樟子松抗寒性测定和不经冷冻处理估测抗寒性的EIS参数,完善EIS法测定抗寒性。以8年生樟子松苗为试材,在抗寒锻炼阶段（10月份）和脱锻炼阶段（3月份）分别取样进行EIS和EL测定。结果表明,EIS法胞外电阻率（re）与EL法测定的樟子松抗寒性相关性较高（R2=0.97）,但比EL法求出的抗寒性高。针叶的细胞膜时间恒量（τm）和茎的弛豫时间（τ1）随冷冻温度变化与re表现相似的S曲线,相关分析表明,re（茎和针叶）与τ1（茎）和τm（针叶）的变化有较好的相关性（R2=0.74～0.84）。经Logistic方程拟合,EIS的τm（针叶）和τ1（茎）法与EIS（re）法、EL法测定的樟子松抗寒性相关性也较高（R2=0.88～0.91）,说明针叶τm和茎τ1也可以作为计算抗寒性的参数。另外,8年生樟子松两个发育时期（10月和3月份）未经冷冻的针叶τm与茎的τ2随抗寒性的增强而显著增加,表明不经过冷冻处理样本用τ2（茎）和τm（针叶）估计樟子松抗寒性是很有前途的方法。