Abstract: The drought-enduring physiological indexes(π_p,ε,etc.)of Pinus sylvestris var.mongolica are measured with 14～16 years old plantations on sandy lands in subhumid semiarid and transitional(from semiarid to arid)regions of inner Mongolia.The results show that thedrought-enduring indexes have a significant regional difference(P≤0.05),which is correlated with local climatic moisture index(I_m),and can be expressed as Y=A+BX (Y,drought-enduring index;X,I_m;and B,variation rate).When I_m is varied from-29.6(Hailar) to -70.2(Huoluo),the variation rate(B)of bulk osmotic potential at initial turgor loss point (π_p) is 0.0034 MPa at early stage of young branch growth and 0. 0061MPa at the last stage of yearly growth period.Similarly,the variation rate(B) of bulk elastic modulus (ε) with I_m is 0.017 and 0.031 MPa,respectively.It is concluded that the drought-enduring property of Pinus sylvestris var. mangolica can be varied and improved by drought trainning.

Key words: Pinus sylvestris var. mongolica, Plantation, Drought-enduring characteristics, Climatic change, MaxEnt, giant panda, species distribution model, Biomod2