重要值

主要研究结果如下：（1）以植物重要值、Simpson指数、Shannon-Wiener旨数、Pielou指数以及Sorenson相似性指数，对紫金山6个主要森林群落进行了研究。

Followings are the main results . ( 1 ) The important value , Simpson index , Shannon-wiener index , Pielou evenness index and Sorenson similarity coefficient were applied to study the main forest communities in the Purple Mountain .

物种重要性可以简单地理解为生态系统中物种的重要值，它由三个指数构成，即物种结构重要值（SIV）、功能重要值（FIV）和动态重要值（DIV）。

The species importance can be simply understood as the important value of species in the ecosystem , which consists of three indexes : species structural important value ( SIV ), functional important value ( FIV ) and dynamical important value ( DIV ) .

采用样方法取样，依据重要值指标运用双向指示种分析（TWINSPAN）法，将山西中条山中段植被群系分成16个群丛。

62 samples collected in Midpiece of Zhongtiao Mountains were classified into 16 associations by Two-way Indicator Species Analysis ( TWINSPAN ) .

滩地造林使原优势种芦苇（Phragmitesaustralis）和荻（Miscanthussacchariftorus）的重要值和生物量都有所下降；

Afforestation on beach land leaded to IV and biomass of dominant species ( Phragmites australis and Miscanthus sacchariftorus ) decreased in the herb community .

聚类分析结果，当相关系数R≥0.90时，以重要值为特征的植物聚合为10类，它们分别属于植物群落不同演替阶段的建群种、优势种和伴生种。

The clustering analysis results show that when the correlation coefficient R ≥ 0.90 , the plant species taking importance value as characteristic are grouped into 10 types , belonging to constructive plants , dominant plants , and associated plants of different successive phases of plant communities respectively .

不同海拔高度高山绣线菊种群的优势度变化不大，在3050m～3250m区间其重要值超过了头花杜鹃种群。

The dominance of Spiraea alpina in the different altitude was almost the same and IV of it was more than that of Rhododendron capitatum from 3050m to 3250m .

并且做出了乔、灌木重要值的排名。

And made the rank of Joe , bush important value .

小叶章群落以小叶章为优势种，其重要值为50.8%。

Angustifolia community , with the important value 50.8 % .

重要值的改进及其在羊草群落分类中的应用

Amending of importance value and its application on classification of Leymus chinensis communities

因此，应该首先将输入文档中的重要值置入变量。

So , put important values from your input document in variables first .

天山北坡低山草地复合体植物群落重要值差异分析

Analysis on Important Value of Phytocoenosis of Low-elevation Grassland in Northern Slope of Tianshan

不同季节的相对重要值最大的种不同。

The species of the greatest relative importance values differ in the four seasons .

湖南长沙生态入侵植物群落重要值研究

Study on the Importance Value of Exotic Plants Community in Changsha of Hunan Province

相比群落优势种，豆科植物在灌丛群落的重要值均很小。

Compared to the dominant species , the important values of legume plants are very small .

杭锦旗甘草群落中甘草占绝对优势，甘草重要值达到0.26；

The dominant species in the community at Hangjinqi are G.uralensis of which the important value is0.26 .

在海岸青皮林群落内，青皮的相对密度、相对优势度、重要值大大高于其他物种。

Coastal Vatica hainanensis forest in Shimei Bay was a strongly mono-dominant forest with low species diversity .

施氮对退化天然草地主要物种地上生物量和重要值的影响

Effect of Nitrogen Fertilizer on Biomass and the Important Values of the Main Species in Degraded Grassland

在低植物密度生境中，物种多样性随密集型和游击型克隆植物相对重要值的增加而增加。

In plant-spare habitats , Shannon-Wiener index increases with increasing importance of phalanx and guerilla clonal plants respectively .

通过对适宜评价图和利用现状图的空间叠加，计算、分析了待调整土地资源的多度及重要值。

The current land use map and suitability evaluation map were analyzed contrastively using GIS spatial analysis function .

青檀是乔木层优势树种之一，其重要值达66%。

Pteroceltis tatarinowii , one of dominant species of arborous layer had important value ( 66 % ) .

朗乡林区原生主要林型中主要树种的重要值随海拔高度明显的变化规律。

The importance values of main species in primary forest stand and the elevation follow the regular patterns .

试验结果表明：沙打旺从兴盛到衰败，出现一快速演替系列，其重要值有明显的变化。

The survey showed that the life of Astragalus adsurgens from thrivingness to decline is a rapid succession series .

植被群落优势种为刺槐，其胸高断面积和重要值方面均表现出明显的优势度。

The statistics of breast-height basal area and the important value showed that Robinia pseudoacacia was obviously dominant species .

在群落样方调查的基础上，计算群落物种重要值，确定群落类型。

Based on the sampling investigation and calculating important value of all samples , three types of communities were confirmed .

重要值在林分郁闭前逐渐增加而后减少的植物种组成了侵入种组，包括75种喜光植物；

The invasive species group included 75 light-loving species , which increased their density before stand closed and afterwards decreased .

植被基带群落中，在物种数量、区系成分和重要值方面，常绿和落叶阔叶树种所占的比例都相差无几。

Evergreen and deciduous broad-leaved tree species were almost equivalent in quantity and importance values in the basal vegetation zone .

放牧主要降低多年生植物的重要值，且降低幅度很大，一年生植物的重要值有小幅增加。

Grazing main reduces the important value of perennial plant and minor increase the important value of annual plant . 3 .

主要种群的生态位宽度和重要值之间也存在着显著正相关关系。

And there was also very significantly positive correlation between the niche breath and the important value of main tree populations .

从重要值上看，乔灌类占30.93%，短命植物占45.73%。

In terms of important value , arbor and shrubs account to 30.93 % and ephemerals acount for 45.73 % . 2 .

乔木以栓皮栎占绝对优势，其重要值最高，优势度明显；

Quercus variabilis is absolutely dominant in the tree stratum , its importance value is the heighest and the superiority is obvious .