title: [Root growth dynamics of Adenophora potaninii populations and its relation with environmental factors in northwest Sichuan Province].
abstract: In this paper, the dynamics of the root biomass and form development of Adenophora potaninii populations in different natural habitats in Northwest Sichuan were studied, and the factors influencing the root growth and form development were analyzed. The root biomass accumulation process of the mean individuals of the whole A. potaninii population in its life could be expressed by Logistic equation. From 1-3 years, the root length grew fast, but the root biomass accumulated slowly. From 4 years old, the root system developed in high speed, and the fast growth period of the root system could maintain until 15 year old. The basic patterns of root biomass accumulation process of different A. potaninii populations at different altitudes were similar to that of the whole population. However, the root system accumulation and root development was related closely with habitant conditions, and the root forms of different populations at different altitudes were significantly different (P < 0.05). At middle altitude (2800-3300 m), the biomass and form of root system could achieve a higher level, and the good harvest of root biomass could be obtained because of the favorable soil and climate conditions, and the less external disturbance of human beings. Therefore, this area could be an important base for A. potaninii population to grow. Whereas at the lower altitude (2600-2800 m), the biomass accumulation and the form development of root system were confined and maintained at a lower level because of the drought climate and the external disturbance of human beings. At the higher altitude (3300-3500 m) area with the harsh habitats, especially with lower temperature and lower pH, the root biomass of the mean individuals was significantly lower, and the individual form of root system was smaller, compared with that at middle altitude area. In order to use natural A. potaninii resource sustainablely, all the area should be planned, and the reasonable rotational prohibition of grazing and digging should be carried out.
authors.affiliation: Tianjin Normal University, Tianjin 300074, China. zwhckh@public.xa.sn.cn
authors.forename: Wenhui
authors.initials: W
authors.lastname: Zhang
authors.forename: Xiangjun
authors.initials: X
authors.lastname: Liu
authors.forename: Guobin
authors.initials: G
authors.lastname: Liu
authors.forename: Keming
authors.initials: K
authors.lastname: Ma
mesh_terms: D000531:Altitude; D018533:Biomass; D029422:Campanulaceae / Q000254:growth & development*; D018517:Plant Roots / Q000254:growth & development*