EFFECT ON POPULATION DYNAMICS TO HALOXYLON PERSICUM

IN DIFFERENT EDAPHIC TYPES

 

YUYANG SONG^*, XIAOJING HU AND CHAOBIN ZHOU

 

Department of Forestry, Agricultural College, Shihezi University, Shihezi, Xinjiang, 832003,China

Postal address: Department of Forestry, Agricultural College, Shihezi University

Road of North 4th, Shihezi city, Xinjiang 832003,China

*Corresponding author’e-mail: syy.agr.shzu@126.com; Phone(fax): +8609932061061.

 

Abstract

 

This study investigated the age class structure of H. persicum populations in different edaphic types in Gurbantünggüt desert and  analyzed the survival rate, mortality rate and spectral analysis characteristics. The results showed that the survival curve of H. persicum populations tended to be the type of Deevey-Ⅲ, the mortality rate of H. persicum was high at early stage and low at late stage, There existed 2-4 death peak phases in the whole population life span. The natural regeneration process of the H. persicum population can be represented by the fluctuation of the distribution of the number of trees in different age classes. Spectral analysis showed that the fluctuation of H. persicum population was multi-harmonic superposition with large periodic containing small periodic, and had more than two periodic fluctuation. Upscaling process of spectral analysis indicated that the periodic fluctuation of H. persicum population becomes constant in relatively small sampling plot (4400-5600 m²), when it is growing under relatively good environmental conditions in the Gurbantünggüt desert. On the other hand, when the growing conditions are poor, large plot (4000-9200 m²) is needed to obtain constant population. Accordingly, different plot sizes should be used for spectral analysis to reveal the periodic fluctuation on the optimal scale.

 

Key words: Haloxylon persicum, Periodic fluctuation, Spectral analysis, Scaling analysis.