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991.
本文对昆嵛山老杨坟阳坡与阴坡半天然植被植物群落的上层(乔木层)和下层(灌木层)的物种优势度、多样性指数、群落的均匀度、相似性指数以及群落的最小面积进行了分析。昆嵛山老杨坟半天然植物群落上层的最小面积应为300m2,下层应为225m2。阳坡与阴坡植物群落的上层和下层优势种的分布格局存在一定差异;乔木层的物种多样性指数,阴坡大于阳坡,灌木层阳坡大于阴坡,但二者的差异水平不显著;两群落乔木层的均匀度指数存在显著差异。阳坡与阴坡植物群落乔木层的相似性指数低于灌木层,并且以相对盖度和相对优势度(相对重要值)为基础统计所得到的群落相似性指数更好地反映了群落间乔木层在结构和功能上的差异。 相似文献
992.
中国新记录光藓科Schistostegaceae植物在长白山的发现 总被引:1,自引:0,他引:1
本文报道了中国新记录光藓科Schistostegaceae植物光藓Schistostega pennata(Hedw.)Web. et Mohr在长白山的发现,并对其形态特征和生态环境进行了描述和讨论。 相似文献
993.
Pollen analysis of five moss patches collected from the forest floor on West Mountain of Kunming (N 24˚57', E 102˚37') provided informations about the quantitative relations between pollen content and coverage of principal plant taxa. Vegetational data with coverage are estimated from each sampling site within the range of 30 m. Trees were calculated in percentage of the total arboreal, herbs and ferns are respectively computed as percentages of the latter two sorts. A preliminary R-value was estimated. According to the difference of R-values, the pollen types could be divided into two groups: 1. R> 1, means overreprsented the type containing Pinus, Alnus, Cyclobalanopsis, Artemisia, and ferns; 2, R <1, means under-represented the type containing Keteleeria and Michelia. But the differences in the values for RPinus, RAlnus etc. in five samples reflected the significant differences in pollen productivity or pollen dispersal efficiency of Pinus, Alnus, etc. Therefore, the ratio of R-value was equal. Five genera have been calculated. The relative R-values for five tree species were: Ra:Rb:Rc:Rd:Re=l:21:5:25:30 (a. Keteteeria; b. Cyclobalanopsis; c. Castanopsis; d. Pinus and e. Alnus). These computations are only a rough estimate because the samples are too few. 相似文献
994.
Lang Kai-Yung 《植物分类学报:英文版》1985,23(6):418-428
The Gongga Mountain Region, located on the eastern fringe of QinghaiXizang Plateau and at the north-eastern end of Hengduan Mountains, is one of the
well-known large mountain areas in Sichuan Province. There are forty five high peaks
with the elavation of 6000 m or over in the area, among which the Gongga Mountain
is the highest one, with its summit being at the altitude of 7556 m, whereas the Dadu
River Valley in the eastern part of the area is only 1150 m above sea level; The relative height in the region is thus about 6400 m.
As we know so far the orchids in Gongga Mountain Region comprise 34 genera and
75 species with 1 variety, of which 12 species are epiphytes, 59 species with 1 variety
terrestrials and 4 species saprophytes (Table 1.).
I. The geographical distribution in the Gongga Mountain Region.
The vertical distribution of the orchids in the area.
Eastern flank: There are 39 species with I variety of orchids at 1150-2300
(-2400) m alt. in the subtropical evergreen broadleaf forest zone, of which 12 species,
such as Bulbophyllum andersonii, Dendrobium hancockii, Otochilus porrecta, etc., are
epiphytic (including a semiepiphyte, Pleione bulbocodioides), 25 species with 1 variety,
such as Bletilla formosana, Calanthe davidii, Cypripedium henryi, etc., are terrestrial,
and 2 species are saprophytic (i.e. Gastrodia elata and Neottia listeroides), the upper
limit of the real epiphytic orchids is 1800 m alt. At the altitude 2300(-2400)-3600
(-3800) m, in the coniferous forest zone, found are 23 species, including 20 terrestrial
species with 1 variety, such as Amitostigma gonggashanicum, Calanthe fimbriata, Coeloglossum viride, etc., 2 saprophytic species (Neottia acuminata and Risleya atropurpurea) and one semiepiphytic species. There are only 2 terrestrial species (i.e. Cypripedium tibeticum and Orchis chusua) at 3600(-3800)-4000m alt., in alpine shrub zone,
the upper limit of the terrestrial orchids being 4000 m alt. At 4000-4400 m alt., in
alpine meadow zone no orchids have so far been found.
Western flank: There are 14 species of orchids, such as Habenaria limprichtii,
Hemipilia flabellata, Satyrium ciliatum, etc., at 2300-2800 m alt., in the river valley
shrub zone, and they all belong to the terrestrial orchids. At the altitude of 28003800m, in the coniferous forest zone found are 19 species of orchids, among which 18
species are terrestrial (such as Amitostigma monanthum, Cephalanthera longifolia, Peristylus coeloceras, etc.) and one is saprophytic. There are only 4 species of terrestrial
orchids (i.e. Cypripedium tibeticum, Gymnadenia orchidis, Orchis chusua and O. diantha) at 3800-4800 m alt., in the alpine shrub-meadow zone, the upper limit of vertical
distribution of terrestrial orchids being 4400 m alt. Twelve species here are common
to the eastern flank.
II. The floristic composition of orchids in Gongga Mountain Region.
1. Twenty three species, belonging to 13 genera, are widespread in Whole EastAsian Region.
2. Eight species, belonging to 8 genera, are the elements of the Sino-Japanese
Subregion.
3. Forty one species with 1 variety, belonging to 24 genera, are the elements of
the Sino-Himalayan Subregion, more than five times the elements of the Sino-Japanese
Subregion.
4. The floristic features of the orchids in the area.
(1) The floristic elements are mainly temperate and subtropical ones.
(2) The life form is mostly terrestrial.
(3) The species endemic to China are prolific (35 species with 1 variety, belonging to 18 genera, are endemic to China, and 26 species with 1 variety are distributed
in south-western China and its adjacent region; Amitostigma gonggashanicum is endemic
to the area).
The floristic composition of orchids in the area is characterized by the dominance
of terrestrial species and temperate and subtropical East-Asian elements, though with
a few Indo-African tropical elements (such as genus Satyrium (1 species) ).
In conclusion, it may be considered that the species of orchids are abundant and
floristic elements are comparatively complex in the Gongga Mountain Region. 相似文献
995.
【目的】揭示禁牧处理对西藏亏祖山温性草原优势植物群落中主要植物物种的生态位和种间联结的影响,为青藏高原温性草原植物多样性保护和科学管理提供理论依据。【方法】采用“Levins”方法、方差比率法(Vr)、卡方检验、联结系数(Ac)和Ochiai(Oi)指数,对亏祖山温性草原优势植物群落中的8个主要植物物种进行分析。【结果】(1)禁牧增加了草沙蚕(Tripogon bromoides)、高山嵩草(Carex parvula)、白草(Pennisetum flaccidum)和丝颖针茅(Stipa capillacea)的生态位宽度和生态位重叠值。(2)研究区内禁牧处理的群落总体表现为负关联(Vr=0.43),自然放牧群落总体表现为正关联(Vr=1.21);χ2检验表明8个优势物种所组成的28个种对在禁牧和自然放牧处理下分别有67.9%和53.6%的种对表现出负联结性;联结系数Ac值表明,禁牧和自然放牧处理下分别有50%和42.9%的种对均... 相似文献
996.
Pengfei Fan Qingyong Ni Guozheng Sun Bei Huang Xuelong Jiang 《Primates; journal of primatology》2009,50(1):37-44
The diet of a habituated group of black crested gibbon (Nomascus concolor jingdongensis) was studied from March 2005 to April 2006 in the Wuliang Mountains, central Yunnan, China. Gibbons consumed 77 different
plant species, one mammal-, two bird-, one lizard-, and two insect-species. Buds and leaves constituted 46.5% of the diet
(21.0% vine leaves and buds, 19.2% tree leaves and buds, and 6.3% epiphyte leaves). Fruits, figs and flowers accounted for
25.5, 18.6 and 9.1% of the diet, respectively. There was marked seasonal variation in dietary proportions. Fruit varied from
0.3 to 82.7%; figs from 0 to 68.2%; tree leaves and buds from 1.5 to 83.3%; vine leaves and buds from 3.1 to 61.9%; and epiphyte
leaves from 0 to 22.2% of the diet. Different food types dominated the diet in different months during the study period. The
foli-frugivorous diet and extreme seasonal variation in the diet may be related to the harsh habitat of the study group. 相似文献
997.
亏祖山秋季不同海拔土壤纤毛虫优势种生态位及其与环境因子的关系 总被引:1,自引:0,他引:1
为深入了解拉萨河流域亏祖山不同海拔梯度秋季土壤纤毛虫优势种生态位及其与环境因子的关系,于2015年10月在亏祖山共设置11个样点,用土壤采样器采用梅花五点式采集土样,同时记录相应的理化因子,土样在实验室自然风干后,采用"非淹没培养法"和"活体观察法"进行培养和形态学鉴定。亏祖山11个样点中,共鉴定到土壤纤毛虫132种,隶属3纲14目48科66属,其中14个优势种(Y>0.02)。土壤纤毛虫优势种生态位宽度最大的是明显长颈虫(Dileptus conspicuus),生态位宽度最小的是卵圆前管虫(Prorodon ovum)和似肾形虫(Colpoda simulans)。土壤纤毛虫优势种生态位重叠值位于0.02-0.99之间,生态位重叠值最低的为似肾形虫(Colpoda simulans)和卵圆前管虫(Prorodon ovum),而生态位重叠值最高的为念珠角毛虫(Keronopsis monilata)和膨胀肾形虫(Colpoda inflata)。亏祖山14个优势种生态响应速率之和为负值,表明土壤纤毛虫优势种处于衰退阶段。土壤纤毛虫优势种与环境因子的典范对应分析(CCA)结果显示,轴1和轴2累计解释物种变异的37.8%,表明轴1和轴2能较好地反映优势种与环境因子的关系;总氮是显著解释变量,对优势种变异的解释率为17.6%。综上分析得出,明显长颈虫(Dileptus conspicuus)、点滴半眉虫(Hemiophrys pectinata)和前口瞬目虫(Glaucoma frontata)对土壤环境适应能力较强,具有广泛的生态适应幅度;土壤纤毛虫优势种生态位重叠值低,种间竞争比较弱;土壤纤毛虫优势种之间以及优势种和环境之间尚未达到相对的动态平衡,优势种正处衰退阶段;总氮是影响拉萨河流域土壤纤毛虫优势种分布和生态位的主要环境因子。 相似文献
998.
999.
大别山区谷底平原生态系统的特征及社会发展中的若干问题 总被引:1,自引:1,他引:0
分析了大别山区谷底平原生态系统的组成与功能 ,探讨了该区在社会发展中存在的水土流失、环境污染、耕地浪费和生物多样性单调等若干问题。建议通过适当外迁部分人口 ,发展现代有机农业 ,依靠科学技术 ,走农业综合化之路 ,以真正实现大别山区谷底平原的可持续发展。 相似文献
1000.