A study of coarse woody debris (CWD) in an Abies fargesii forest in the Qinling Mountains showed that, 1) the total amount, the annual average increment and the decomposition rate of CWD in the forest were 15 848 t·hm -2 ,1 877 and 1 310 t·hm -2 ·a -1 respectively.
In morphology,there are 14 arbor species (1 evergreen,13 deciduous),9 shrub species (2 evergreen, 7 deciduous),7 liana species (1 grassy,6 woody , 1 evergreen stunned or shrub species, 2 decciduous stunned or strub species and 24 herb species. In all of these exclusive species ,there are 11 that distribute in the area extensively.
An extreme low level of genetic variation was revealed both at the species level(A=1.21,P=21.05%,H_e=0.040)and at population level(P=14.04%,A=1.14(0.04),H_e=0.036 (0.018) ), which were lower than those of long-lived perennial woody and narrowly distributed species.
4. Abies pollen was under-represented and could spread only a short distance. Under Abies forest,the pollen made up only 19.5 per cent of the total pollen of herbs and trees, and 21.7 per cent of woody plants.
They were used to estimate the population respiration, and the result showed that the annual population respiration amount was 57 868 t·CO 2 hm 2 a 1 , of which the stem 4 449, the branch 4 695, the root 6 868, the leaf 41 855 t·CO 2 hm 2 a 1 . the respiration amount of the leaf was the highest accounting for 72 33%, of the other woody organs were lower only accounting for 7 69%～11 87%.
The differences between woody organisms of stems, roots, and soils excluding roots were statistically significant (p>amp;lt;0.05), indicating that heterotrophic respiration from microorganism activity may be more sensitive to global warming.
The duration of the period with leaves slightly affects the temperature sensitivity of woody organisms since the Q10 values for root and stem of coniferous evergreen trees did not differ significantly from deciduous trees (p>amp;gt;0.10).
Relationships between xylem embolism and eco-physiological indices in eight woody plants in situ (II): The relationship with pho
It was discussed that this bidirectional promoter could possibly be applied in woody plant engineering.
Concept and Classification of Coarse Woody Debris in Forest Ecosystems