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基于野外实地栽植试验,对重庆市万州区消落带历经1 a、3 a、6 a水淹后的中山杉在各水淹高程的保存率及树高、胸径、地径和冠幅进行研究。结果表明:(1)1次水淹后,166~175 m高程段内中山杉的保存率为100%;3次水淹后,168~175 m高程段保存率为100%;6次水淹后,170~175 m高程段保存率为98%。(2)中山杉的树高、胸径、地径和冠幅总体上随高程的降低而变小;但在一定高程范围内,水淹胁迫程度变强反而会促进中山杉树高的生长。(3)水淹初期,水淹对中山杉生长的影响显著;随着水淹次数增多,水淹对中山杉的影响不显著。(4)中山杉在地势低洼地带的保存率明显降低,但在根系裸露的条件下仍能正常生长。(5)中山杉能够改善土壤理化性质,有利于防止消落带水土流失。
Based on field experiments in the field, the preservation rates, tree height, DBH, crown diameter and crown width of Zhongshangshan (Cunninghamia lanceolata) after flooding for 1 a, 3 a, 6 a in Wanzhou District, Chongqing were studied . The results showed that: (1) After 1 flooding, the preservation rate of A. sinensis in the elevation range of 166-175 m was 100%; after 3 flooding, the preservation rate of 168-175 m elevation segment was 100%; 6 flooding After 170 ~ 175 m elevation segment save rate of 98%. (2) The height, DBH, ground diameter and crown width of Zhongshan fir decreased with the elevation decreasing. However, within a certain elevation, the degree of flooding increased but it would promote the growth of Zhongshan fir. (3) In the initial period of flooding, flooding had a significant impact on the growth of A. cristata. With the increase of flooding frequency, the flooding had no significant effect on A. cristata. (4) Zhongshan fir in the low-lying areas of the preservation rate was significantly reduced, but under the bare root conditions can still grow normally. (5) Zhongshan fir can improve soil physical and chemical properties, is conducive to preventing the water level erosion.