Effect of Forest Gap on Regeneration of Dominant Species in Malan Forest Area on the Loess Plateau

Forest gap disturbs the forest structure and dynamics of forest.Quercus liaotungensis and Pinus tabulaeformis are the dominant species in the main community types in Malan forest area on the Loess Plateau.In this paper,the seedlings and saplings of these two species in various-sized forest gaps are measured,and the seedlings and saplings in gaps and under the canopies are compared and analyzed.The results show that these two dominant species have different regeneration strategies,that is,Q.liaotungensis regenerates its population by relying on its high germination,while P.tabulaeformis regenerates its population by reducing the mortality rate of its seedlings and saplings.When the gap area is 20-40 m2,the natural regeneration of P.tabulaeformis is the best,but the natural regeneration of Q.liaotungensis in various-sized gaps is more complex.Forest gap disturbance can promote the natural regeneration of these two dominant species.In the future,the dominance of the Q.liaotungensis and P.tabulaeformis in the Q.liaotungensis forest and P.tabulaeformis forest will not be replaced each other by forest gap disturbance.So Q.liaotungensis and P.tabulaeformis in the Q.liaotungensis forest and P.tabulaeformis forest will exist for a long period as the succession climax and subclimax in this area.