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Study on Neighborhood Interference and Competition Characters of Larix Chinensis

Author: DuanRenYan
Tutor: WangXiaoAn
School: Shaanxi Normal University
Course: Ecology
Keywords: L.chinensis Abies The scope for competition Gradually expand the scope of law Succession Morphological plasticity
CLC: S718.5
Type: Master's thesis
Year: 2005
Downloads: 120
Quote: 2
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Abstract

Larix chinensis (Larix chinensis) is a second-class protected species endemic to China, the distribution is extremely limited, only distributed in 2600 to 3600m above sea level within the scope of the Shaanxi Qinling Mountain. It is the only tree species the Qinling most on-line is an important part of the ecological system, plays an important role in water conservation, solid rocks, soil and water conservation. The competition is one of the main plant morphology, structure, life history and dynamic changes, when environmental resources can not meet the maximum demand of plants, plant competition. Plant competition between plant population and community ecology theoretical basis for the guidance of species conservation is important. The plant has solid growth characteristics determine its competition often occurs in the neighborhood between plants, the competition among the neighborhood plants, also known as the neighborhood interference. On L.chinensis neighborhood interference with the competitive nature of the research, not been reported. This paper carried out a more systematic study, the main conclusions are summarized as follows: 1 gradually expand the scope of the method of different diameter class genet subject of neighborhood competition intensity (average intensity of competition and the intensity of competition) and the scope of relationship, the result is the the: ① neighborhood average intensity of competition decreases with the increase in the scope of the impact, decreased rapidly within a certain range, and outside this range, the decrease is reduced, may use this as the basis to determine the scope of the neighborhood ; ② genet diameter class neighborhood zone there are some differences; in the ignore diameter case, L.chinensis neighborhood range from 6m; (3) o the total intensity of competition and the extent of the relationship between obedience on logarithmic function (CI = the ALNC B). The results show that, gradually expand the scope of the method can effectively determine the scope for competition, put forward a range of new methods of determining plant competition in the neighborhood. 2 most of the studies have shown that no competition index for the species should be selected based on their corresponding competitive index. The research L.chinensis: (1) competition index there is some connection; (2) through a comparative analysis of four kinds of plant competition index prediction, Zhang Yue West (1993) contains the object DBH competition DBH and objects of wood and competitive tree distance competition index can objectively reflect the competition between Larix chinensis community plants. 6m scope for competition, Zhang Yue West competition index quantitative analysis of the Larix chinensis intraspecific and interspecific competition intensity. The results show that: (1) with the object of wood (genet) diameter at breast height increases, due to the density of Larix chinensis populations thinning process of regulation, plant distance increases, intraspecific competition intensity decreases; the ② L.chinensis distribution at higher elevations, community within other species less the individuals generally small, relatively weak interspecific competition, intraspecific and interspecific competition order: L.chinensis - L.chinensis gt; Abies (Abies fargesii) - L.chinensis gt;, leather birch (Betula utilis) - L.chinensis gt; other species - L.chinensis. (3) competitive strength of the object DBH relationship follows a power law function of (CI = the AD ^{-B ), when the the Larix chinensis diameter at breast height of 35cm or more, almost no change in the intensity of competition resulting prediction model can be better predict the intensity of competition in the of Larix chinensis species within and between species.}

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