Relationships between woody plant diversity and environmental factors in the Golhisar (Burdur) district

This study was addressed to examine the relationships between environmental factors and plant diversity components ((i.e. average alpha diversity (?), beta diversity (ß) and gamma diversity (?)) of each of all different live zones of forest stands(i.e. tree layers, upper shrub layers, lower shrub layers and, all live form layers) in the Gölhisar district of the Mediterranean region, Türkiye. The field inventory method was based on a nested sampling. A sample area about an area of 0.6 km2 (750x750 meter) was taken corresponding to a cell size of bioclimatic data. To calculate diversity components, four sample plots (20x20 meter) were taken in each sample area. The data was collected from 160 sample plots into 40 sample areas. Woody plant species and their coverage classes were recorded at each live zone in each sample plot. Environmental variables of sample plots were also recorded in the course of the field works. Explanatory variables of sample areas were also prepared by obtaining climatic data from wordclim.org, by calculating variations of some variables recorded from sample plots and by creating produced variables via digital elevation model. Multiple regression analysis (MLR) and regression tree technique (RT) were applied to explain the variations of response variables. The results of RT were found much better that the results of MLR. According to the results obtained from RT, altitude was appeared in all the tree model of all ? response variables. Soil skeleton amount contributed to the tree models of ? tree layer, ? upper shrub layers and ? all live form layer while soil depth was found in the models of ? tree layer, ? lower shrub layer and ? all live form layer. With regards to ß , Sample area variation coefficient of elevation was found the most important factor because this variable contributed to built the models of ß tree layer, ß lower shrub layer and ß all live form layer. Four climatic variables contributed to the models of ? response variables as well as sample area variation coefficients of heat index, landform, altitude, slope degree, soil dept, , aspect favourability