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In this paper, the distribution of three species of beech forests, regarding their
position on differently facing slopas and at different elevations, as well as their pollen
distribution, on Fanching Shan situated in Kweichow Province in South-eastern
China is discussed.
It is the fact that (1) Being affected by the air currents of the Pacific Monsoon,
and by its own topographic variation, the difference between the north and south
slopes in its eastern and western flanks reflected on the plant communities by the
humidity-warmth relationships (fig. 2, 3; tab. 2, 3, 4). (2) The patterns of the hori-
zontal distribution of three species in China show that Fagus engleriana has a
northern-most range, F. longipetiolata the southern-most range, while F. lucida is
intermediate between them (fig. 5). (3) From the palynological analysis of the soil
layers, the waxing and waning of the different tendencies of Fagus spp. on different
slopes are rather prominent.
The discussion is made mainly as follows. The relationship between the state of
growth and humidity-warmth conditions is shown (fig. 6). In accordance with the
conditions of the vertical, horizonal and palynological distribution of beeches, we have
tried to present a figure (fig. 7) which shows the waxing and waning tendencies of
three species of Fagus historically, with respect to different slopes. The southern
slope of western flank (Ws) is now in a state moderate growth of Fagus longipetio-
lata; in the past, there had been a period which saw this beech enjoying a gradual
increase, but later on it began to wane till it reaches the present state. The Wn slope
had seen a gradual increase of Fagus lucida in the historical time (at the same time
there was an accompanying slow increase of F. longipetiolata), till a certain period
when the total number of beech pollen grains decreases gradually in the analysis;
this is followed again by a slight increase, the last increase is apparently due to the
fact that in spite of the decrease of F. lucida, there was a great increase in F. longi-
petiolata. The two effects combine to make the line of curve to lower rather than
to rise. The Es slope has in its historical past a period when beeches were favoured
with a steady increase, and this tendency is apparently still in progress today,
although it is approaching its culmination. The En slope had seen Fagus engleriana
in a slowly receding tendency, and sees it now almost in the process of being eli-
minated, to be replaced by F. lucida. Through the explanation given above, we have
thereby an understanding about the relationship between the climatic changes in the
historical time and the waxing and waning of the different beeches in both time andspace. 相似文献
2.
从企业的管理实践中,我们会发现这样一个规律:企业中80%的业绩往往是由20%的优秀员工完成的,这就是所谓的“帕雷托法则”。GE公司的前总裁韦尔奇正是基于此理论提出了著名的“精英团队”管理理念,也就是通过不断淘汰业绩差的员工,来增加优秀员工的比例,从而把20%的优秀员工比例不断扩大,也正是这些优秀的员工铸就了GE公司今日的辉煌。如何增加20%优秀员工的比例呢?在这个令人困扰的管理难题背后,其实意味着企业管理水平的差距,有的企业经营多年,关键职位始终是那几个人,优秀员工的数量有减无增;而有的企业却能够通过各种方式来培养关键职… 相似文献
3.
陵川县潞城联区,是一个山区公社,全社27个大队,75个自然村,办有44所中、小学校。1981年9月以来,他们先在全公社建立岗位责任制,82年冬季又在上郊中心学区试行改革教学管理工作,从1983年3月起,在全社范围内推广实行了落实教学责任、加强学校管理的教学双保合同制。通过推行教学双保合同制,在全社范围内不仅小学在完成“三率”(入学率、巩固率、合格率),中学在完成“双重任务”方面取得了初步效果,而且大 相似文献
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5.
鄂西神农架地区的植被和植物区系 总被引:1,自引:0,他引:1
Shennungia is generally known as “The highest mountain in Central China”. It is
situated at latitude 31°342'N., longitude 110°35'E. in western Hupeh.
The area explored is deeply cut in all sides by five V-shaped valleys, giving the
landscape a steep topography. Its summit is about 3105 meters above the sea level, and
the relative altitude is from 1000-2000 meters.
The climate of the region is warm temperate. The differences of humidity-warmth
condition between the eastern and the western flanks are quite marked.
In western Hupeh and the adjacent area of Szechuan the rugged topography still
preserves some tracts of natural forests at higher elevations. Our vegetational survey
is confined to localities above 1500 meters. The collection of plant samples of the flora
is extended to the whole mountain from the foothill to the peak. The present article
deals with only a part of the results of our survey.
1. The vertical vegetation belts of Mt. Shennungia and relationships with other
regions: The vegetation belts on the eastern and the western flanks of the mountain
are shown in diagram 2 and 3. The comparison of the vertical vegetation zones of the
Mt. Shennungia with those of the Yülungshan in N. W. Yunnan and the eastern
Himalaya to the west and with those of Hwangshan and Central Japan to the east
is shown in table 4, It shows that the plant communities of the Mt. Shennungia are of
temperate nature, and they are more closely related to those of Hwangshan in S.
Anhwei and of Central Japan than to the eastern Himalaya.
2. Floristic composition: The generic ranges of flowering plant are relatively
distinct and stable. Various distributional patterns of genera are analysized.
1) Statistics of the genera in various distributional patterns: The total number
of genera of flowering plants in this region are 762, belonging to the following four
categories. A) tropical genera 239 (31.3%), B) temperate genera 416 (54.7%), C)
endemic genera 47 (6%), and D) comsmopolitan genera 61 (8%).
2) Endemic genera: An examination of the composition of the flora in western
Hupeh reveals that 47 endemic Chinese genera occur in this mountain of which 24 are
monotypic genera, 20 oligotypic and 2 multitypic as shown in Table 4. The arborescent
genera are nearly all deciduous. They are of temperate nature.
3) Temperate genera: There are 416 genera in wastern Hupeh. They are
subdivides into the following three groups according to their distributional patterns:
A) The north temperate genera: There are 159 genera belonging to 62 families in
western Hupeh. B) Eastern Asian genera: There are 117 genera belonging to 69
families in western Hupeh. Among them 22 are common to the western Szechuan,
adjacent regions of Yunnan and the Eastern Himalaya. The remaining 95 genera are
commom to both eastern China and Japan. C) The Eastern Asian-eastern North-
American genera: Of the total 762 genera known in western Hupeh, 64 are disjunc-
tively distributed in both eastern Asia and eastern North-America.
4) The tropical genera: Of the 762 genera of the flowering plant of western
Hupeh, 239 (31%) are of tropical nature.
Finally, our survey shows: 1. Many of the primitive temperate genera and ende-
mic relicts concentrate in western Hupeh and the adjacent region of Szechuan indica-
ting that it might be one of refuges of tertiary flora. Moreover, it might also be one
of the most important regions of differentiation, development and distribution of tem-
perature flora. 2. The vegetation of this region is not only of temperate nature, but
also of a transitional nature. 3. According to an analysis of the flora and a compari-
son of the vertical distribution of the vegetation of Yülungshan and Eastern Himalaya
to the west with Hwangshan and Central Japan to the east, the floristic affinity of
western Hupeh is more closely related to eastern China and Central Japan rather than
to the Eastern Himalaya, and phytogeographically this region is intermediate between
the Sino-Himalayan and the Sino-Japanese patterns. However, the problem of phyto-
geography of western Hupeh and the adjacent region of Szechuan is a complicated
one requiring further study.
相似文献
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