بررسي پوشش زيراشكوب در محيط هاي تحت كشت سياه تاغ در منطقه اردستان

Investigation on Understory Vegetative Cover in Haloxylon aphyllum Plantation Area in Ardestan Region, Iran

As the recognition impact of a plant specie plantation in a specific area can determine the effect s of that plant in oth er parts and area s of the country , the effects of Haloxylon plantation on the stand understory in de sert lands of Ardestan were studied . Three areas of Haloxylon plantation and a re ference site which were approxima tely similar in terms of altitude (height), slope, soil, and geomorphology have been selected . The necessary number of plots in each area was chos en on stati stical base. In this study the plant den sity and crown closure o f the understory spec ies in the Haloxylon stand and also , th e reference area wer e measured. Then , by using Dan kan Test and Analysis of Variance through SPSS packa ge the achieved data of the sampling were analyzed. Th e study conducted that there was a significant difference between the und erstory coverage of plantation areas and the reference site. It is concluded tha t the Haloxylon plantation cau sed a great deal of inc reasing in understory species number and composition.