Abstract: In this paper, LANDIS model was used to study the effects of different management strategies on the larch (Larix gmelinii) forests of Tuqiang Forest Bureau on the northern slopes of Great Hing’an Mountains after the catastrophic fire in 1987. Three management strategies,i.e., natural regeneration if the catastrophic fire in 1987 was not happened (M₁), natural regeneration after the catastrophic fire in 1987 (M₂), and current management strategy after the catastrophic fire in 1987 (M₃), were compared over a 300year period. The results showed that the abundance of larch forests over 300 simulation years under the three management strategies had significant difference. In the whole Bureau, the abundance of larch forests under M₂ was obviously lower than that under M₁ and M₃ over 300 years, and the abundance under M₃ was lower than that under M₁ at the beginning. Due to the reforestation after the catastrophic fire in 1987, the abundance of larch under M₃ increased rapidly, and caught up with that under M₁ after about 100 years. In addition, different forest management strategies also had significant influence on the age structure of larch forests, especially for mature and overmatured larch forests. The abundance of mature and over-matured larch forests under M₁ was higher than that under M₂. This abundance under M₃ had tremendous decrease because of forest harvesting for about 10 years, and then, increased with time and would exceed that under M₁ and M₂ for over 100 years. Furthermore, in unburned areas and burned areas, the -abundance of mature and over-matured larch forests also had significant difference over 300 simulation years under the three management strategies.

Key words: yield, drip irrigation frequency, irrigation amount, water use efficiency, potato, quality