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61.
In many German forest soils low base saturation of CEC in deeper soil layers was reported and acidic deposition is seen as
the major cause of these findings. To test this hypothesis we sampled 5 New Zealand forest soils from pristine beech (Nothofagus fusca, N. menziesii, N. solandri) sites under climatic and geological conditions comparable to higher elevations in Germany. The soils developed from granite
and greywacke. Soil samples were analyzed for pH and the exchangeable cations were extracted with 1M NH4Cl. The base saturation of all soil profiles was very low, even in deeper layers and was thus similar to the patterns found
in many German forest soils. The pH was generally higher in the New Zealand soils as compared to Germany. The reason for the
depletion of base cations in deeper soil layers of New Zealand forest soils is most likely the leaching of base cations with
HCO3
- resulting from the dissociation of carbonic acid in connection with high amounts of seepage. Thus, under high rainfall conditions,
the low base saturation found in deeper layers of forest soils cannot exclusively be attributed to the effects of acidic depositions
and land use. ei]Section editor: R F Huettl 相似文献
62.
Mike H. Jurke 《Primates; journal of primatology》1996,37(1):109-119
The fate of most nonhuman primate species is intimately related to man. The increasing encroachment on the natural habitat
has resulted in the decimation and even near extinction of some species. Along with this development, the basic concept in
many modern zoos has changed from one of merely display to self-perpetuating units. Primate research facilities are orienting
their research programs towards reproductive physiology and behavior in an effort to provide basic knowledge of reproduction
in these species. This increased emphasis in the area of reproductive biology and the various efforts to improve breeding
of these mostly endangered primates in captivity has stimulated the author to write this review. It represents an attempt
to provide the reader with basic background information relating to the endocrinology and behavior of reproduction in the
clawed New World monkeys as it exists at the time of publication.
The intermediate evolutionary position ofCallimico goeldii between the clawed New World monkeys and the ‘true New World monkeys’ and our relatively poor knowledge about reproduction
and behavior in this particular species fully justifies the focus on Goeldi’s monkey in this essay. This review is an attempt
to provide a brief history of previous studies but also the basis for research in the future. The current status of knowledge
of the small-bodied clawed monkeys is also discussed in an evolutionary context, with an emphasis on the different reproductive
strategies in this dynamic group of primates.
The outcome, not surprisingly, confirms the unique position ofCallimico goeldii in its social, ecological, and evolutionary environment. 相似文献
64.
中国蟹蛛科(蜘蛛目)新种记述 总被引:1,自引:0,他引:1
记述我国蟹蛛科花蟹蛛属6新种和蟹蛛属2新种,共计8新种,金林花蟹蛛Xysticusjinlin,玛纳斯花蟹蛛X.manas,林芝花蟹蛛X.nyingchiensis,拟斑花蟹蛛X.parapunctatus,似旋花蟹蛛X.torsivoides,吴氏花蟹蛛X.wuae,广西蟹蛛Thomisusguangxicus和胡氏蟹蛛T.hui。 相似文献
65.
66.
鼎湖山珠甲螨属1新种(蜱螨亚纲:甲螨亚目:珠甲螨科) 总被引:1,自引:0,他引:1
记述我国广东省鼎湖山珠甲螨属1新种,命名为叉珠甲螨,新种Damaeus(Tectodamaeus)furcatusWangetLu,sp.nov。 相似文献
67.
中国紫金牛属一新种 总被引:1,自引:1,他引:0
胡启明 《热带亚热带植物学报》1995,3(4):13-16
中国紫金牛属一新种胡启明(中国科学院华南植物研究所,广州510650)关键词紫金牛属;光萼紫金牛;新种ANEWSPECIESOFARDISIAFROMCHINA¥HuChiming(SouthChinaInstituteofBotany,Academ... 相似文献
68.
丘华兴 《热带亚热带植物学报》1995,3(4):17-22
作者清理采自中国南部大戟科标本过程,发现一些需增补的分类群,现报道其中2个新种:分布于广东封开县的印禅铁苋菜Acalyphawui和印禅三宝木Trigonostemonwui;2个新纪录种:分布于云南勐海县的短序白桐树Claoxylonsubsessiliflorum和生长于海南南沙群岛的南沙大戟Euphorbiareniformis;1个近代生长于广东、贵州和四川的归化种-桃叶猩猩草Euphorbiaheterophylla,而将依据四川渡口的标本命名的柳叶大戟E.epilibiifolia作为它的新异名. 相似文献
69.
1992年11月15日从云南省河口县城自由市场的一位越南人手中买得一雌性巨蜥,经鉴定为一新种,定名为越南巨蜥Varanusvietnamensis。鉴别特征:新种背部鳞片光滑,仅在后半部插有极少的起棱鳞片,不同于V.nebulosus(Boulenger,1885,1890;Taylor,1963);新种不同于V.salvator在于其背部没有眼斑状横斑带(ocellimarks)(Guenther,1864;Harrison等,1957;Pope,1935);不同于V.irrawardicus(Yang等,1987),V.griseus和V.monitor(Smith,1935)在于有6─7个横向扩大的眼上鳞。文中运用了15个外部性状对产于南亚,东南亚大陆及岛屿共9个种(含新种)的种间亲缘关系进行了研究,结果认为,种间亲缘关系的亲疏与分布地区相距的远近成正相关。 相似文献
70.
云南小孢发属地衣的分类 总被引:3,自引:0,他引:3
报道了云南小孢发属地衣13种,其中中国新记录种6个,它们是:喜马拉雅小孢发,尼泊尔小孢发,光滑小孢发,光亮小孢发,多叉小孢发,波氏小孢发,另外7种的形态及分布也在文中进行了讨论。 相似文献