ABSTRACT
This study was carried out by the methods of typical plots investigation and laboratory test aiming at analyzing the survival state and fruiting characteristics of three Sinopodophyllum hexandrum populations in different environmental habitats. Meanwhile, it could provide scientific basis for enhancing wild population quantity recovery. The results showed that more population quantity grow in the habitats of large-area gap (Population A) and bushes (Population C) with a majority of the young individuals, while the minor-area gap (Population B) was the opposite. The development tendency of S. hexandrum populations would be the recession in the future. Spatial distribution pattern of populations was clumped at small scales but random at large scales. The indexes of population A and C, as fruit size，the quantity and quality of seeds，germ inability，were all superior to those of population B. Comparing the mainly environment factors of three populations, that favorable environmental factors for vegetative and reproductive growth of S. hexandrum populations were found，especially certain lighting intensity and fertile soil. Therefore, the favorable environmental habitats for S. hexandrum individuals growth could be artificial to promote the recovery and quantities of S. hexandrum populations in the future.
ABSTRACT
To study photosynthetic characteristics and its influencing factors in leaves of medicinal plant Mirabilis himalaica, and provide an evidence for guiding artificial planting and improving the quantity. The light-response and diurnal photosynthesis course of leaves at the booting stages of 1-3 year old M. himalaica were measured with LI-6400 system. The Results showed that the light response curves were fitted well by non rectangle hyperbola equation (R2 > or = 0.98). The values of the maximum photosynthetic rate (Pmax) and light use efficiency of three-year old M. himalaica leaves were higher than those of 1-2 year old individuals. The diurnal variation of net photosynthetic rate (Pn) and stomatal conductance (Gs) of 2-3 year old M. himalaica were typical double-peak curves determinately regulated by stomatal conductance. However, transpiration rate (Tr) of 1-3 year old plants leaves were single-peak curve, which was self-protection of harm reduction caused by the higher temperature at noontime. Correlation analysis showed that the changes between photosynthetic active radiation (PFD), air temperature (T ) and Pn, were significant positive related. Therefore, M. himalaica is a typical sun plant, which should be planted under the sufficient sunshine field and prolong the growing ages suitably in order to improve the yield.