Nine microsatellite DNA primers for Hippophae rhamnoides ssp sinensis (Elaeagnaceae)

Hippophae rhamnoides ssp. sinensis occurs mainly in the and regions of northwest China. The wood stands of this subspecies play an important role in maintaining the local ecosystems in these regions. In addition, the genetic characteristics are essential to understand the historical range changes of this subspecies and its morphological differentiation with other subspecies. In this study, we developed nine microsatellite loci for this subspecies for the first time. We used the combining biotin capture method to enrich AG/CT/AC/GT/CG/GTG/CCA microsatellites. Twenty-six microsatellites were isolated from the enriching library and nine of them were found to be polymorphic through screening 12 distantly distributed individuals. The number of alleles per locus ranged from three to twelve and expected heterozygosity from 0.2659 to 0.4767, respectively. We further performed cross-priming tests in another subspecies and two congeneric species. These firstly isolated loci will provide a useful tool to investigate the genetic structure of this subspecies and its morphological differentiation from the other subspecies.

Molecular evidence for double maternal origins of the diploid hybrid Hippophae goniocarpa (Elaeagnaceae)

Homoploid hybrid plant species are rare, and the mechanisms of their speciation are largely unknown, especially for homoploid hybrid tree species. Two contrasting hypotheses have been proposed to explain the origin of Hippophae goniocarpa: (1) it is a diploid hybrid originating from H. rhamnoides ssp. sinensis x H. neurocarpa ssp. neurocarpa, and (2) it originated via marginal differentiation from H. rhamnoides ssp. sinensis. Regardless of which of these hypotheses is true (if either), previous studies have suggested that H. rhamnoides ssp. sinensis is the only maternal donor for this hybrid species. In this study, we aim to elucidate the maternal composition of H. goniocarpa and to test the two hypotheses. For this purpose, we sequenced the maternal chloroplast DNA trnL-F region of 75 individuals representing H. goniocarpa, H. rhamnoides ssp. sinensis, and H. neurocarpa ssp. neurocarpa in two co-occurring sites of the taxa. Seven haplotypes were identified from three taxonomic units, and their phylogenetic relationships were further constructed by means of maximum parsimony, maximum likelihood, and network analyses. These seven haplotypes clustered into two distinct, highly divergent lineages. Two haplotypes from one lineage were found in H. rhamnoides ssp. sinensis, and five (representing the other lineage) in H. neurocarpa ssp. neurocarpa. Hippophae goniocarpa shared four common haplotypes from both lineages, but the haplotypes detected from the two populations differed to some extent, and in each case were identical to local haplotypes of the putative parental species. Thus, both H. rhamnoides ssp. sinensis and H. neurocarpa ssp. neurocarpa appear to have together contributed to the maternal establishment of H. goniocarpa. These results clearly demonstrate that the marginal origin hypothesis should be rejected, and support the hybrid origin hypothesis. Hippophae goniocarpa exhibits a sympatric distribution with its two parent species, without occupying new niches or displaying complete ecological isolation. However, this species has effectively developed reproductive isolation from its sympatric parent species. Our preliminary results suggest that H. goniocarpa may provide a useful model system for studying diploid hybrid speciation in trees. (c) 2008 The Linnean Society of London.

新疆天山中段北部空中花粉数量的时空变化及其气候与植被指示意义

空中花粉是植被类型、气候状况与大气环境质量的指示物之一。空中花粉雨的取样实验对化石花粉谱的解释和古植被的恢复具有指导意义，因此空中花粉分析成为第四纪孢粉学和古生态学研究的有效辅助手段。本研究在新疆天山中段北坡进行了短期的空中花粉监测（2001年7月~2006年7月），目的是获得局域性和区域性植被所散发的花粉类型及其数量信息，并探讨花粉数量的植被与气候指示意义、花粉传播以及受环境条件影响的程度，同时分析和检测花粉浓度受气候条件的影响情况。空中花粉的收集使用Cour-type捕捉器，分别在3个不同海拔梯度进行5年连续的空中花粉收集（夏秋季节每周一个样品，冬春季节每两周一个样品）。取样地点分别是新疆天山中段北部的天池气象观测站（43°53'58.38"N, 88°07'15.75"E , 海拔1942.5m）、中科院阜康荒漠生态系统定位站（44°17'27.41"N, 87°55'52.65"E, 海拔477m）和准噶尔盆地古尔班通古特沙漠南缘的北沙窝试验站(44°22'40.74"N, 87°55'9.74"E, 海拔443m），取样点的植被带跨度天山北坡的森林草原到低海拔的典型荒漠。 光学显微镜鉴定的空中花粉主要有43种类型（24科30属），而蕨类、苔藓与真菌孢子数量较少。孢粉类型多样性指数为2.45（Shannon Index）。显然，从样品中所鉴定的空中花粉种类与所观察的植物种类有很大的差距。花粉类型与数量在三个不同海拔梯度的取样点上也有明显差异。天池取样点的花粉类型较丰富，与天山北坡垂直带植被分布以及丰富的植被成分相对应，花粉的优势种类为雪岭云杉(Picea schrenkiana)、蒿属(Artemisia)、藜科(Chenopodiaceae)、柽柳科(Tamaricaceae)和麻黄属(Ephedra)，高代表性的外源荒漠花粉类型“削弱了”本地花粉类型的代表性;阜康与北沙窝取样点的花粉类型主要来自荒漠成分的藜科、蒿属、麻黄属、蒺藜科(Zygophyllaceae, 白刺属Nitraria为主）、柽柳科（柽柳属为主）、蓼科(Polygonaceae, 沙拐枣属Calligonum为主）等耐旱植物。花粉数量与植被数量并非简单的线性关系。空中和表土花粉的数量分析表明，藜科、蒿属、麻黄属花粉具有超代表性;雪岭云杉花粉的代表性适中;禾本科(Gramineae)、榆属(Ulmus)、白刺属、柽柳科、沙拐枣属花粉代表性较差。 5年平均花粉浓度大小依次是阜康（81.668 grains/100m3）>天池（51.726 grains/100m3）>北沙窝（45.7685 grains/100m3）。蒿属花粉的峰值出现在秋季，并且出现双峰现象（可能与不同蒿类花期分布不均有关），而其它木本和草本类植物花粉浓度的峰值为单峰，具有明显的季节性，春夏之交开花的桦木属、榆属等类型较为明显。藜科花粉的峰值出现在夏季，麻黄和柽柳的峰值出现在盛夏，桦木属、柳属Salix、雪岭云杉等花粉浓度峰值出现在初夏，与其花期物候相对应。木本植物花粉以雪岭云杉为主，其次为桦木属(Betula)、榆属、柳属、胡颓子科(Elaeagnaceae)花粉，柳属花粉百分比在三个取样点分配比较均匀，桦木属花粉在空间分布上差异明显，与植物分布数量相关。胡颓子科的花粉出现时间短，数量也较少。榆属花粉出现的季节性明显，代表性也较差。因此解释地层中出现类似的低代表性和高代表性的花粉类型时，需要注意其百分比数量的适当校正。木本植物花粉百分比随海拔高度变化成正比关系，对植被的指示性较好。雪岭云杉的年平均花粉浓度在天池取样点明显高于其它两个取样点，5年的平均花粉浓度和百分比与海拔高度呈正比。天池取样点的百分比最高为28.85%，平均为21.15%，而北沙窝与阜康两地5年平均百分比含量分别为0.69%和1.57%，这种时空变化规律与植被数量的关系密切。藜科花粉百分比在阜康和北沙窝取样点占绝对优势，5年的平均花粉浓度与海拔高度呈反比。蒿属花粉年平均浓度与海拔高度关系微弱（R2=0.04，p =0.46），而花粉百分比与海拔高度有显著的线性正比关系（R2=0.72，p<0.0001）。但在低海拔的两个取样点之间差异不明显。 年平均花粉百分比和花粉浓度随海拔梯度而变化，主要花粉类型的变化规律存在差异。暗针叶林雪岭云杉花粉的年平均百分比在低海拔的阜康和北沙窝地区低于3%，在盛花期的6月初，低海拔的取样点也未见超过5%，雪岭云杉花粉的传播在研究区范围内数量分布变化较大，再次表明该类型的花粉在原地沉积效率很高。空中花粉数量能够较好地指示主要的植被带，盛花期内50%以上的雪岭云杉花粉含量则指示了雪岭云杉森林植被带，而高含量的蒿属植物花粉指示了天山山前冲积平原上的蒿类荒漠，相反，高含量的藜科花粉代表了低海拔地区的荒漠。雪岭云杉花粉百分比与浓度均与海拔高度呈显著的线性正比关系，表明雪岭云杉花粉传播的局限性。主要的非木本植物藜科花粉的浓度与海拔高度成反比，蒿属则相反，表明藜科与蒿属花粉在研究区具有很好的植被与气候指示意义。 花粉绝对数量、百分比、浓度具有明显的年际变化，其原因与气候状况的变化有关，年平均花粉浓度、主要类型的花粉浓度与气候参数（降水量、平均温度、最高和最低温度、相对湿度等）的相关分析表明，降水量和湿度与花粉浓度呈负相关程度较高，与其它气候参数则呈显著的正相关。干旱指数、花粉比值、花粉百分比（AP，NAP）与七月份平均气温，年平均降水量的相关系数（Pearson correlation），Ar/Ch与七月平均温度在0.01水平上呈显著的正相关（R2=0.894）, 与年平均降水量在0.01水平上呈显著的负相关（R2=0.874）。AP花粉百分比与七月份平均温度呈显著的负相关（R2=0.71, p<0.0001），与年降水量呈正相关（R2=0.43, p=0.01），而NAP花粉正相反。利用短期监测的空中花粉雨数据计算得到的花粉比值以及干旱指数在研究区具有明确的指示意义，尤其是干旱指数、Ar/Ch、Ar/Ep，这些都可为表土花粉、植被与气候关系模型的建立提供重要的参考信息。 气候参数在很大程度上影响大气花粉的浓度，而风速和风向对空中花粉的传播、散布影响较大，花粉的来源与传播受风向和风速的控制。不同取样点的空中花粉数量差异受地形条件影响很明显，这种差异也可利用地形空气动力学特征的差异来解释，天池监测站因“逆坡”（upslope）的气流促进了低海拔的花粉流向高海拔传播。 研究区的空中花粉数量信息是研究表土花粉、植被和气候关系以及第四纪古生态学的重要基础。本研究提高了对研究区空中孢粉的类型及其传播规律的认识和理解，增加了解空中花粉受环境影响的主要因素及其影响程度，对地层孢粉类型鉴定和花粉数据的解释提出指导性建议，对本地区的古植被与古环境研究增加现代孢粉学的参考依据和信息，并可为建立区域性的现代孢粉－植被－气候关系模型提供可靠依据。 同时，本报告也讨论了存在问题和不足，并提出了今后工作的可能完善方案。

中国沙棘(Hippophae rhamnoides subsp. sinensis)天然群体的遗传变异分析

近十年，植物群体遗传学的研究飞速发展，然而与海拔相关的植物群体遗传结构和遗传变异研究却相对较少。到目前为止，还不清楚遗传变异与海拔之间是否有一个通用的格局。在山区，各种生态因子，如温度、降水、降雪、紫外线辐射强度以及土壤成分都随海拔梯度急剧变化，造成了即使在一个小的空间区域，植被类型变化显著，这种高山环境的异质性和复杂性为我们研究植物群体遗传结构和分化提供了方便。沙棘(Hippophea)属于胡颓子科(Elaeagnaceae)为多年生落叶灌木或乔木，雌雄异株，天然种群分布极为广泛。中国沙棘(H. rhamnoides subsp. sinensis)是沙棘属植物中分布较广的一个亚种，种内形态变异非常丰富，加之其具有独特的繁育系统和广泛的生态地理分布，是研究沙棘属植物遗传变异和系统分化的理想材料。本文从1,800 m 到3,400 m 分5 个海拔梯度进行取样，用RAPD 和cpSSR 分子标记研究了卧龙自然保护区中国沙棘天然群体的遗传结构和遗传变异。5 个取样群体依次标记为A、B、C、D 和E，它们分别代表分布在海拔1,800，2,200，2,600，3,000 和3,400 m 的5 个天然群体。RAPD实验用11 条寡核苷酸引物，扩增得到151 个重复性好的位点，其中143 个多态位点，多态率达94.7%。在5 个沙棘群体中，总遗传多样性值(HT)为0.289，B群体内的遗传多样性值为0.315，这完全符合沙棘这种多年生、远交的木本植物具有高遗传变异的特性。5 个群体内遗传多样性随海拔升高呈低－高－低变异趋势，在2,200 m海拔处的B群体遗传多样性达最大值0.315，3,400 m海拔处的E群体则表现最小仅0.098。5 个群体间的遗传分化值GST＝0.406，也即是说有40.6%的遗传变异存在于群体间，1,800 m海拔处的A群体与其它群体的明显分离是造成群体间遗传分化大的原因。UPGMA聚类图和PCoA散点图进一步确证了5 个群体间的关系和所有个体间的关系。最后，经过Mantel检测，遗传距离与海拔表现了明显的相关性(r = 0.646, P = 0.011)。cpSSR 实验中，经过对24 对cpSSR 通用引物筛选，11 对引物能扩增出特异性条带，只有2 对引物(ccmp2 和ARCP4)呈现多态性。4 个等位基因共组合出4 种单倍型，单倍型Ⅰ出现在A 群体的所有个体和B 群体的8 个个体中，C、D、E 三个群体均不含有，而单倍型Ⅱ出现在C、D、E 三个群体的所有个体及B 群体的18 个个体中，A 群体不含有。另外两种单倍型Ⅲ和Ⅳ为稀有类型，仅B 群体中的4 个个体拥有。这种单倍型分布模式和TFPGA 群体聚类图揭示了，C、D、E 群体可能来源于同一祖先种，而A 群体却是由另一祖先种发展起来的，B 群体则兼具了这两种起源种的信息，这可能是因为在历史上的某一时期，在中国沙棘群体高山分化的过程中，B 群体处某个或者某些个体发生了基因突变，具备了适应高海拔环境的能力，产生了高海拔沙棘群体的祖先种。 In recent ten years, studies about population genetics of plants developed rapidly,whereas their genetic structure and genetic variation along altitudinal gradients have beenstudied relatively little. So far, it is uncleared whether there is a common pattern betweengenetic variation and altitudinal gradients. In the mountain environments, importantecological factors, e.g., temperature, rainfall, snowfall, ultraviolet radiation and soil substratesetc., change rapidly with altitudes, which cause the vegetation distribution varying typically,even on a small spatial scale. The mountain environments, which are heterogeneous andcomplex, facilitate and offer a good opportunity to characterize population genetic structureand population differentiation.The species of the genus Hippophae L. (Elaeagnaceae) are perennial deciduous shrubs ortrees, which are dioecious, wind-pollinated pioneer plants. The natural genus has a widedistribution extending from Northern Europe through Central Europe and Central Asia toChina. According to the latest taxonomy, the genus Hippophae is divided into six species and12 subspecies. The subspecies H. rhamnoides ssp. sinensis shows significant morphologicalvariations, large geographic range and dominantly outcrossing mating system. Thesecharacteristics of the subspecies are favourable to elucidate genetic variation and systemevolution. To estimate genetic variation and genetic structure of H. rhamnoides ssp. sinensisat different altitudes, we surveyed five natural populations in the Wolong Natural Reserve at altitudes ranging from 1,800 to 3,400 m above sea level (a.s.l.) using random amplifiedpolymorphic DNA markers (RAPDs) and cpSSR molecular methods. The five populations A,B, C, D, and E correspond to the altitudes 1,800, 2,200, 2,600, 3,000 and 3,400 m,respectively.Based on 11 decamer primers, a total of 151 reproducible DNA loci were yielded, ofwhich 143 were polymorphic and the percentage of polymorphic loci equaled 94.7%. Amongthe five populations investigated, the total gene diversity (HT) and gene diversity within population B equaled 0.289 and 0.315, respectively, which are modest for a subspecies of H.rhamnoides, which is an outcrossing, long-lived, woody plant. The amount of geneticvariation within populations varied from 0.098 within population E (3,400 m a.s.l.) to 0.315within population B (2,200 m a.s.l.). The coefficient of gene differentiation (GST) amongpopulations equaled 0.406 and revealed that 40.6% of the genetic variance existed amongpopulations and 59.4% within populations. The population A (1,800 m a.s.l.) differed greatlyfrom the other four populations, which contributes to high genetic differentiation. A UPGMAcluster analysis and principal coordinate analyses based on Nei's genetic distances furthercorroborated the relationships among the five populations and all the sampling individuals,respectively. Mantel tests detected a significant correlation between genetic distances andaltitudinal gradients (r = 0.646, P = 0.011).Eleven of the original 24 cpSSR primer pairs tested produced good PCR products, onlytwo (ccmp2 and ARCP4) of which were polymorphic. Four total length variants (alleles) werecombined resulting in 4 haplotypes. The haplotype was present in all individuals of Ⅰpopulation A and 8 individuals of populations B, the other three populations (C, D and Epopulations) did not share. The haplotype was present in all individuals of populations C, D Ⅱand E and 18 individuals of populations B, population A did not share. The other twohaplotypes and were rare haplotypes, which were only shared in 4 individuals of Ⅲ Ⅳpopulation B. The distribution of haplotypes and TFPGA population clustering map showedthat the populations C, D and E might be origined from one ancestor seed and population Amight be from another, whereas population B owned information of the two ancestor seeds. Itwas because that gene mutation within some individual or seed in the location of population Bwas likely to happen in the history of H. rhamnoides, which was the original ancestor of thehigh-altitude populations.

(Table 1) Species abundance at DSDP Hole 63-467

Neogene palynofloras of southern California have been all too infrequently studied. Previous investigations of Pacific Coast sediments have been largely restricted to Pacific Northwest locales. Some important studies include those by Gray (1964), Wolfe, Hopkins, and Leopold (1966), Wolfe and Leopold (1967), Hopkins (1968), Piel (1969, 1977), Ballog, Sparks, and Waloweek (1972), and Musich (1973). The only published study of southern California materials is that of Heusser (1978) on Holocene sediments of the Santa Barbara basin. Most of these studies are concerned with the microflora from a particular formation; thus they have limited stratigraphic value and in most cases involve nonmarine to marginal marine rocks where no planktonic zonation was available. Musich's (1973) study was the first attempt at tying pollen assemblages to a planktonic zonation over an extended stratigraphic interval (Miocene to Pleistocene).Its location in the southern California Borderland and the sedimentary sections sampled make Leg 63 extremely valuable in deciphering the palynologic history of the Pacific Coast Neogene. Site 467 was chosen for our initial detailed study, because the relatively slow sedimentation rate provides an almost complete Neogene sequence of mainly terrigenous sediments and reliable planktonic age control is available.The goals of this study were to: (1) establish a reference section of Neogene palynomorph assemblages; (2) develop biostratigraphic criteria for use in correlation with other localities; (3) correlate the palynologic assemblages with the planktonic zonations; and (4) study the paleoenvironmental history in the southern California Neogene.

Miocene microflora and palaeoclimatic estimates of the Stetten section (Austria)

Pollen analyses have been proven to possess the possibility to decipher rapid vegetational and climate shifts in Neogene sedimentary records. Herein, a c. 21-kyr-long transgression-regression cycle from the Lower Austrian locality Stetten is analysed in detail to evaluate climatic benchmarks for the early phase of the Middle Miocene Climate Optimum and to estimate the pace of environmental change. Based on the Coexistence Approach, a very clear signal of seasonality can be reconstructed. A warm and wet summer season with c. 204-236 mm precipitation during the wettest month was opposed by a rather dry winter season with precipitation of c. 9-24 mm during the driest month. The mean annual temperature ranged between 15.7 and 20.8 °C, with about 9.6-13.3 °C during the cold season and 24.7-27.9 °C during the warmest month. In contrast, today's climate of this area, with an annual temperature of 9.8 °C and 660 mm rainfall, is characterized by the winter season (mean temperature: -1.4 °C, mean precipitation: 39 mm) and a summer mean temperature of 19.9 °C (mean precipitation: 84 mm). Different modes of environmental shifts shaped the composition of the vegetation. Within few millennia, marshes and salt marshes with abundant Cyperaceae rapidly graded into Taxodiaceae swamps. This quick but gradual process was interrupted by swift marine ingressions which took place on a decadal to centennial scale. The transgression is accompanied by blooms of dinoflagellates and of the green alga Prasinophyta and an increase in Abies and Picea. Afterwards, the retreat of the sea and the progradation of estuarine and wetland settings were a gradual progress again. Despite a clear sedimentological cyclicity, which is related to the 21-kyr precessional forcing, the climate data show little variation. This missing pattern might be due to the buffering of the precessional-related climate signal by the subtropical vegetation. Another explanation could be the method-inherent broad range of climate-parameter estimates that could cover small scale climatic changes.

Pollen and non-pollen palynomorph records of the Holocene part of the composite sediment core TMD from lake Tso Moriri (NW India) and of modern surface samples from the Tso Moriri region

The high-altitude lake Tso Moriri (32°55'46'' N, 78°19'24'' E; 4522 m a.s.l.) is situated at the margin of the ISM and westerly influences in the Trans-Himalayan region of Ladakh. Human settlements are rare and domestic and wild animals are concentrating at the alpine meadows. A set of modern surface samples and fossil pollen from deep-water TMD core was evaluated with a focus on indicator types revealing human impact, grazing activities and lake system development during the last ca. 12 cal ka BP. Furthermore, the non-pollen palynomorph (NPP) record, comprising remains of limnic algae and invertebrates as well as fungal spores and charred plant tissue fragments, were examined in order to attest palaeolimnic phases and human impact, respectively. Changes in the early and middle Holocene limnic environment are mainly influenced by regional climatic conditions and glacier-fed meltwater flow in the catchment area. The NPP record indicates low lake productivity with high influx of freshwater between ca. 11.5 and 4.5 cal ka BP which is in agreement with the regional monsoon dynamics and published climate reconstructions. Geomorphologic observations suggest that during this period of enhanced precipitation the lake had a regular outflow and contributed large amounts of water to the Sutlej River, the lower reaches of which were integral part of the Indus Civilization area. The inferred minimum fresh water input and maximum lake productivity between ca. 4.5-1.8 cal ka BP coincides with the reconstruction of greatest aridity and glaciation in the Korzong valley resulting in significantly reduced or even ceased outflow. We suggest that lowered lake levels and river discharge on a larger regional scale may have caused irrigation problems and harvest losses in the Indus valley and lowlands occupied by sedentary agricultural communities. This scenario, in turn, supports the theory that, Mature Harappan urbanism (ca. 4.5-3.9 cal ka BP) emerged in order to facilitate storage, protection, administration, and redistribution of crop yields and secondly, the eventual collapse of the Harappan Culture (ca. 3.5-3 cal ka BP) was promoted by prolonged aridity. There is no clear evidence for human impact around Tso Moriri prior to ca. 3.7 cal ka BP, with a more distinct record since ca. 2.7 cal ka BP. This suggests that the sedimentary record from Tso Moriri primarily archives the regional climate history.

Monographie de la famille des Élæagnées /

"Lue a l'Académie des sciences de l'institut, le 7 décembre 1823."

Pollen and spores of sites GeoB8331 and GeoB8323, Namaqualand Mudbelt, Holocene South Africa

To better understand Holocene vegetation and hydrological changes in South Africa, we analyzed pollen and microcharcoal records of two marine sites GeoB8331 and GeoB8323 from the Namaqualand mudbelt offshore the west coast of South Africa covering the last 9900 and 2200 years, respectively. Our data corroborate findings from literature that climate developments apparently contrast between the summer rainfall zone (SRZ) and winter rainfall zone (WRZ) over the last 9900 years, especially during the early and middle Holocene. During the early Holocene (9900-7800 cal.yr BP), a minimum of grass pollen suggests low summer rainfall in the SRZ, and the initial presence of Renosterveld vegetation indicates relatively wet conditions in the WRZ. Towards the middle Holocene (7800-2400 cal. yr BP), a rather moist savanna/grassland rich in grasses suggests higher summer rainfall in the SRZ resulting from increased austral summer insolation and a decline of fynbos vegetation accompanied by an increasing Succulent Karoo vegetation in the WRZ possibly suggests a southward shift of the Southern Hemisphere westerlies. During the last 2200 years, a trend towards higher aridity was observed for the SRZ, while the climate in the WRZ remained relatively stable. The Little Ice Age (ca. 700-200 cal. yr BP) was rather cool in both rainfall zones and drier in the SRZ while wetter in the WRZ.