Study on the Sub-Diurnal Radial Growth of the Populus euphratica
Using the point-dendrometer, automatic meteorological station and the soil water content monitor, the sub-diurnal radial growth of Populus euphratica , intensity of illumination, air temperature, relative humidity and the soil water bulk content in the main root zone were measured synchronously in the riparian divers-leaf poplar forest in the downstream of Heihe River. It is revealed that: 1) the sub-diurnal radial growth of P. euphratica presents a parabola pattern, reaching the lowest in 16:00 - 20:00, and then increasing gradually to the highest in 06 : 00 - 09 : 00 in the next morning. This diurnal cycle can be divided into contraction, expansion and increment phases; 2) the sub-diurnal radial growth of P. euphratica has large difference among different seasons and specimens. The larger of the specimen's diameter, the larger of the net increment is; 3) the intensity of illumination, air temperature and the soil water bulk content have negative relations to the sub-diurnal radial growth of P. euphratica, and the relative humidity has a positive relation. And among them, the relationships of the intensity of illumination, air temperature and the soil water bulk content at the 20 cm depth reach to a high level of significance. These environmental factors, especially the soil water condition, are all likely have the lagged effect on the radial growth of P. euphratica.
point-dendrometer Populus euphraticasub-diurnal radial growthenvironmental factors
NETL
NSTL
万方数据
维普
