生态恢复后的千烟洲植物群落种类组成及结构特征

Qianyanzhou(QYZ) Ecological Station established in 1983 with an area of 204 hm~2 is affiliated to the Chinese Ecosystem Research Network.Before 1982,herbs had been dominant,sparsely dotted with shrubs.After 20-year restoration of the vegetation,the vegetation showed significant changes in both forest coverage and species diversity.Forest coverage had increased to 93.3% in 1999 from 0.4% in 1982.The vegetation could be broadly classified into two groups: artificial forest,accounting for the most percent,and natural secondary forest.These two groups could be subdivided into 12 types.Based on the 2003 field work,The authors studied plant community composition and vertical structure.The results were as follows: 1) On the study plots were there about 150 species,of which 100,49,and 47 grew in arbor layer and shrub layer and herb layer,respectively.Of 12 community types,the amount of species in shrub layer was larger than that of other two layers.As to the species richness in the different community types,Liquidambar formosana community showed the highest and Imperata cylindrical var.major community the least.The amount of species in arbor layer of artificial forest was smaller than those of natural Pinus massoniana forest,but no difference in understory.2) Loropetalum chinense,Quercus fabric and Vaccinium bracteatum were dominant shrub species with a wide distribution.Three ferns Woodwardia japonica、Dryopteris atrata and Dicrannepteris dichotoma were dominant herb species.Lianas were sparse,but Milletlia reticulata were found in all forest types.3) Up to now some natural regeneration species,such as Eurya muricata、Quercus fabri、Vaccinium bracteatum、Rhus chinensis、Adinandra bockiana,had grown in the arbor layer of artificial forests.Some herb species,such as Arundinella setosa、Miscanthus floridulus、Isachne globosa、Scirpus triqueter,which were dominant ones in the herb layer before the restoration of vegetation,disappeared now.4) The vertical structure of natural Pinus massoniana community and Liquidambar formosana community showed more complex comparing with artificial forests.For the artificial forests,the conifer and broad-leaves mixed forest had a more complex structure.In both natural Pinus(massoniana) community and Liquidambar formosana community,it was dominated by individuals with height of 3～4 m,while 10～12 m in the artificial forests.

苏云金杆菌以色列变种防治水处理中摇蚊幼虫研究

研究了苏云金杆菌以色列变种(Bacillus thuringiensis var.israelensis de Barjac,简称B.t.i)用于摇蚊幼虫(即红虫)防治的菌种发酵条件.结果表明,发酵时间为36 h,温度为30℃,摇床转速为250 rpm,三角瓶培养基量为50 mL时,B.t.i对红虫的毒力最强.

小兴安岭针叶树种在不同尺度上对环境因子的敏感性分析

小兴安岭地区是我国重要的林区之一,预测该地区针叶树种的分布,在不同尺度上查找针叶树种分布最敏感的环境因子,是不同层次的林业部门制定森林恢复和植树造林方针的重要科学依据。该文以坡度、坡向、综合地形指数、海拔、坡位指数、年平均温度和年平均降水量作为环境因子,利用Logistic回归模型对红松(Pinus koraien-sis)、兴安落叶松(Larix gmelinii)、冷杉(Abies nephrolepis)、红皮云杉(Picea koraiensis)、鱼鳞云杉(P.jezoensis)和樟子松(Pinus sylvestris var.mongolica)的分布进行了预测。并且采用相对运行特征(Relative operating characteristic,ROC),对模型进行了精度评价。其取值范围为0～1,如果ROC小于0.7,认为模型具有低精度;如果大于0.7且小于0.9,则模型具有较好的模拟精度;如果大于0.9,认为模型具有很高的预测精度。对每个树种的模型验证表明只有冷杉的ROC大于80%,红松、兴安落叶松和云杉的ROC在70%～80%之间,而樟子松的为67.9%。之后,把预测模型应用到丰林保护区,揭示局域尺度上树种分布最敏感的环境因子。经过树种分布预测图与环境因子之间的相关分析发现,在区域尺度(整个研究区)上,红松、冷杉、云杉和樟子松对年降水量最为敏感,而兴安落叶松对坡度最敏感。在局域尺度(丰林保护区)上,红松分布对坡度最敏感,冷杉和云杉对海拔最敏感,兴安落叶松对坡位最敏感。在不同尺度上,树种最敏感的环境因子的转移,引起了在不同尺度上树种分布类型的变化。红松在区域尺度上聚集分布(ROC=78.6%),而在局域尺度上其聚集程度有所减弱(ROC=74.4%),红松的分布范围增加。在区域尺度上,云杉和冷杉聚集分布,但在局域尺度上,它们的分布接近随机分布类型(ROC<60%),它们在丰林保护区内分布面积较大。与以上3个树种相反,兴安落叶松的ROC从71.7%增加到了82.0%,在区域尺度上聚集分布的兴安落叶松,在局域尺度上更加聚集,其分布范围局限于某个特定环境(谷底)。总的来说,在区域尺度上,多数树种分布对气候因子最为敏感,在局域尺度上,对地理因子最为敏感。不同树种对不同环境因子的敏感性,揭示了树种空间分布格局和分异规律。

中国东北蒿属光砂蒿的两个新变种

发表了东北产光砂蒿的两个新变种 ,即疏花光砂蒿 (ArtemisiaoxycephalaKitag .var.sporadanthaW .Wang)和金砂蒿 (A .oxycephalaKitag .var.aureinitensW .Wang)

Solving the coastal eutrophication problem by large scale seaweed cultivation

Eutrophication is becoming a serious problem in coastal waters in many parts of the world. It induces the phytoplankton blooms including 'Red Tides', followed by heavy economic losses to extensive aquaculture area. Some cultivated seaweeds have very high productivity and could absorb large quantities of N, P, CO2, produce large amount of O-2 and have excellent effect on decreasing eutrophication. The author believes that seaweed cultivation in large scale should be a good solution to the eutrophication problem in coastal waters. To put this idea into practice, four conditions should be fulfilled: (a) Large-scale cultivation could be conducted within the region experiencing eutrophication. (b) Fundamental scientific and technological problems for cultivation should have been solved. (c) Cultivation should not impose any harmful ecological effects. (d) Cultivation must be economically feasible and profitable. In northern China, large-scale cultivation of Laminaria japonica Aresch. has been encouraged for years to balance the negative effects from scallop cultivation. Preliminary research in recent years has shown that Gracilaria lemaneiformis (Bory) Daws. and Porphyra haitanensis Chang et Zheng are the two best candidates for this purpose along the Chinese southeast to southern coast from Fujian to Guangdong, Guangxi and Hong Kong. Gracilaria tenuistipitata var. liui Chang et Xia is promising for use in pond culture condition with shrimps and fish.

Settling abalone veliger larvae in a free-swimming microalgal culture

In the current abalone hatchery in China, insufficient diatoms on vertically placed corrugated pvc plates at later stage often could not support the growth of postlarvae up to the stage that they can feed on live macroalgae. As a result, stripping the spats (35 mm) off by anaesthetization and switching the diet from live diatoms to artificial powdered diet in combination has to be performed in most of the abalone farms. This manipulation normally leads to more than 50% mortality. Here we report the direct use of the unicellular green alga Platymonas helgolandica Kylin var. tsingtaoensis as a potential alga to be used to settle the veliger larvae of the Pacific abalone Haliotis discus hannai and to feed the postlarvae. Settlement rate of 2-day-old veliger larvae in mono culture of P helgolandica could be as high as 92% ( +/- 4.2%) on day 10 in small scale trials, higher than that in the selected benthic diatom strain (53.6% +/- 12.7%) when settled in the water in which bacteria propagation was controlled by treatment of 2 ppm of benzylpenicillinum calcium and streptomycin sulfate. Postlarvae fed solely on P. helgolandica or the selected benthic diatom Navicula-2005-A grew at rates of 40.1 ( +/- 1.9) and 45.8 (+/- 13.4) mu m day(-1), respectively, when raised at 22 degrees C until day 50 postfertilization. P. helgolandica was shown to have distinct diurnal settling rhythm characterized with a peak of settled cells in the middle of the night for cell division and a peak of free-swimming cells in the middle of the day. High density of attached P. helgolandica cells on the inner surface of the culture facility in the night fits the nocturnal feeding behavior of the abalone spats. Judged by the promising larvae settling rate, growth and survival rates of the postlarvae fed with this alga, the free-swimming micro-green alga P. helgolandica constitutes a potential species for settling the veliger larvae and for supporting the growth of postlarvae as well. (c) 2006 Published by Elsevier B.V.

海水培养对叶用甜菜形态和生理特性的影响

本文以含有不同浓度海水的50％Hoagland培养液进行叶用甜菜（Beta vulgaris var. cicla L.）的无土培养，并研究了海水培养条件下叶用甜菜多种形态和生理特性的变化情况。结果表明，在电导率相当于22％海水的培养液中生长时，叶用甜菜植株形态和显微结构均无明显变化。在电导率相当于41％海水的培养液中生长时，叶用甜菜仍能保持存活和生长，显微观察也未发现死亡细胞，但植株形态和生理特性发生某些变化：（1）植株形态变化：植株叶面积大大减少，叶片增厚，栅栏组织细胞膨大，根毛变短；（2）植株干重降低，细胞渗透压提高，含水量增加（3）游离脯氨酸的含量比对照增加137％；（4）可溶性糖的含量基本未发生变化；（5）细胞膜电解质渗漏率增大，细胞内离子含量增加；（6）多肽成分变化：24.4KD2和7.0KD多肽的量明显增加；29.1 KD和29.5 KD多肽的表达量则有所减少等。结果表明至少海水培养液电导率相当于22％海水时，叶用甜菜能够正常的生和长，当培养液中盐度过高时，叶用甜菜的形态和生理特性发生某些变经，但仍能生存和长生。同时这些变化也说明叶用甜菜的耐盐性涉及多种生理生化过程，是由体内多种结构和功能协同进行的。

刺瓣绿绒蒿一新变型

[目的]介绍刺辩绿绒蒿的一个新变型.[方法]在青海省花石峡采集绿缄蒿属藏药时发现了刺瓣绿绒蒿(Meconopsis horridula var.spinulifera.)的一个白花新变型,与原变种(总状绿绒蒿Meconopsis horridula var.racemosa)进行了比较.[结果]在青海省玉树州玛多县花石峡生境为海拔4 200m的小河岸边阳坡草地上发现了刺瓣绿绒蒿的白花新变型,与原变种的区别在于花冠白色;花瓣两面中下部疏生细刺;花柱具4棱,棱呈膜质翅状,宽约1.5 mm;花丝窄线形.[结论]发现的刺瓣绿绒蒿新变型与原变型的主要区别是植物花冠呈白色.

国产赖草属（禾本科）两个类群的修订

根据标本研究、野外考察和实验观察，对国产赖草属Leymus两个类群进行了分类修订，将阿尔金山赖草Leymus arjinshanicus D．F．Cui和L．aerginshanicus D．F．Cui ssp．ruoqiangensis（S．L．Lu＆Y.H．Wu）D．F.Cui处理为若羌赖草L．ruoqiangensis S．L．Lu＆YH．Wu的新异名，将纤细赖草L．secalinus（Georgi）Tzvel．var．tenuis L．B．Cai提升为一个独立的种L．tenuis（L．B．Cai）L．B．Cai．

新疆赖草属（Poaceae）两个新变种

报道了新疆赖草属2个新变种，即北疆赖草（Leymus tianschanicus（Drob．）Tzvel．var．borealus L．B．Cai）和短穗赖草（Leymus angustus（Trin．）Pilger vat．brevistachyus L．B．Cai）。

青海补血草属一新变种

在整理蓝雪科标本时,发现了补血草属的一个新变种:玛多补血草(Limonium aureum Hill.var.maduoensis),生境为海拔4000 m以上的滩地紫花针茅高寒草原和盐碱化土壤中.

中国细柄茅属(禾本科)两个新异名和一个新组合

在标本室研究和野外考察的基础上,对中国细柄茅属Ptilagrostis Griseb.几个类群进行了分类修订.双叉细柄茅P. dichotoma Keng ex Tzvelev和窄穗细柄茅P. junatovii Grub.分别被归并到细柄茅P.mongholica (Turcz. ex Trin.)和太白细柄茅P. concinna (Hook. f.) Roshev.中作异名;小花细柄茅P. dichotoma Keng ex Tzvelev var.roshevitsiana Tzvelev则被提升为种P. roshevitsiana (Tzvelev) L. B. Cai.

利用叶绿体DNA trn L-F序列初步探讨菊科风毛菊属的系统发育

风毛菊属Saussurea DC．是菊科物种分化十分剧烈和分类处理十分困难的一个属。该属的单系起源性质、属下分类系统以及一些独特形态物种的系统位置尚不清楚，有待进一步验证。本文测定了代表该属5个亚属37种植物43个样品和川木香属Dolomiaea DC．的1种样品的叶绿体DNA trnL-F序列，并调取菜蓟族Cardueae Cass．与风毛菊属具有一定亲缘关系的13属的该序列，一起进行了分支分析，重点验证该属的属下形态分类系统以及形态特殊、青藏高原地区特有的雪兔子亚属subgen．Eriocoryne中假雪兔子组sect．Pseudoeriocoryne的单系性质。研究结果表明：(1)尽管风毛菊属5个亚属形态变异极大，但种间的trnL-F碱基变异却非常小；(2)根据形态学划分的5个亚属在分支图上没有得到分辨；(3)根据无明显茎、叶呈莲座状包被头状花序等特征建立的假雪兔子组是一多系群，与其他雪兔子亚属的种类也没有密切的亲缘关系，其共同拥有的形态学特征分别起源了4次；(4)雪莲亚属假雪莲组subgen．Amphi- laena sect．Pseudoamphilaena中的多鞘雪莲s．polycolea变种尖苞雪莲S．polycolea var．acuisauama与风毛菊亚属subgen．Saussurea的长毛风毛菊S．hieraciodies、美丽风毛菊s．superba、打箭风毛菊s．tatsienensis和重齿风毛菊s．katochaete具有一段长18个碱基的插入，但多鞘雪莲原变种和重齿风毛菊另一居群无此插入；这一插入在整个菜蓟族和风毛菊属中都十分特殊，是一次进化事件的结果，这一复合体的形态分化应该是在这一进化事件发生之后进行的；而尖苞雪莲和重齿风毛菊拥有这一特殊序列可能是由于杂交而导致种内存在不同的单倍性。研究结果证实青藏高原极端环境下即使在较低的分类等级——属内、种问的形态特征也存在相同选择压力下的生态趋同进化。这一点在利用形态特征研究该地区物种的亲缘关系和命名自然分类等级时应予以特别重视。风毛菊属提供了研究极端环境下物种快速分化、网状进化和趋同进化的典型范例。

甘肃棘豆属一新变种

Oxytropis xinglongshanica C. W. Chang var. obesusi-corollata Y. H. Wu, var. nov. A var. xinglongshanica recedit corollis obesis, vexillis c. 15 mm longis, c. 10 mm latis, limbis late ovatis, unguibus c. 6 mm longis; alis c. 14 mm longis, c. 4.5 mm latis, limbis anguste obovatis.

春小麦新品种高原314及其栽培技术

高原314是中国科学院西北高原生物研究所农业中心通过有性杂交培育的春小麦新品种，2001年12月通过青海省农作物品种审定委员会审定，品种原代号为95-314，现定名为高原314，属小麦Var. graecum Korn的变种。品种组合为：高原602 * {[ST142 * [(82宁182 * 82原11) * 47-2]] * [(78-17-3 * 83-228-3) * (Chanal * 338)]}F_3。