Full-Text Search:
Home|About CNKI|User Service|中文
Add to Favorite Get Latest Update

Realized Niches of Several Eremophytes in Desert Communities of Minqin Desert Area

CHANG Zhao-feng,ZHAO Ming,HAN Fu-gui,ZHONG Sheng-nian (Gansu Key Laboratory of Desertification Combating,Gansu Desert Control Research Institute,Wuwei,Gansu 733000,China)  
Minqin desert area belongs to the typical droughty desert climate and its vegetations are mainly desert shrubs and its vegetation coverage only comes to 5%~15%.In the plant communities,the niche breadths vary greatly and the similarity ratios among different plants are very low.Low niche breadth and similarity ratio,resulting from the conditions of the droughty desert habitats,are one of the major features of sparsely distributing plants in droughty desert ecological environments.The realized-niche breadths of the plants closely relate to the annual rainfalls and soil moisture and are the dominating factor among the other factors such as landforms,soil nutrient and particles.Where water table is about 20 m,the plants can not utilize underground water and the resource competition among the plant species mainly appears as the competition for water resources among which rainfall is key one for the plant species to compete for.The niche breadths of same plants vary greatly among different communities and the competitive relations of the plant species in different communities vary depending on the combined actions of the niches of the species,stable landforms and soil conditions,and annual rainfall fluctuations.The dominant species have the widest niche breadth in the communities,and annual short-life plants many a time get into the communities while the niches of the dominant species decrease.The canopies of the desert plants are simple and thus the proportions of their canopies to the quadrat area are used as their eigenvalues to accurately and reliably calculate the eigenvalues of their niches.
Download(CAJ format) Download(PDF format)
CAJViewer7.0 supports all the CNKI file formats; AdobeReader only supports the PDF format.
©CNKI All Rights Reserved