Study On The Adaptive Of Different Cultivation Models Of Tetraploid Black Locust In TianShui Area

This article took the tetraploid black locust introduced by Tian Shui area in GanSu province as the study object, investigated and analyzed the phenology, growth status and soil water content of the tetraploid black locust plantation in different cultivation models, the results showed that:1.The crown width, standard branch, basal diameter, length of new shoot, and leaf area of tetraploid black locust were all bigger than robinia pseudoaccia L., it is more suitable for being the green manure plant , and the best mowing period is May 20 to June 26. 2.The growth indexes difference of each forest in different cultivation models is significantly, besides the ground diameter, the growth sorting of each index was as follows: the low density pure forest >the high density pure forest >the middle density mixed forest.3.The sorting of annual average soil water content was as follows: the middle density mixed forest> the low density pure forest >the high density pure forest, and the vertical change of the middle density mixed forest's soil water content was the stablist of all.4.The low density pure forest model of tetraploid black locust grew faster, the annual water demand was moderate, it could be applied in the investigated areas with better water condition; the model of middle density mixed forest grew well, the annual water demand was much fewer, the stand structure was stable, could be widely applied in investigated area, the model of high density pure forest grew well situated, but its annual water demand was much higher, so that, it was not situated to be applied in investigated area above.