不同石漠化治理模式的造林保存率及幼林生长分析

Afforestation Preserving Rate and Young Plantation Growth of Different Combating Rock Desertification Models

关键词:  石漠化  造林  顶果木  降香黄檀  纯林  混交林

Key words:  rock desertification  afforestation  Acrocarpus fraxinifolius  Dalbergia odorifera  pure plantations  mixed plantations

摘要:

[目的]了解不同石漠化治理模式对林分造林成活率、保存率及幼林生长的影响。[方法]通过两种树种(顶果木Acrocarpus fraxinifolius、降香黄檀Dalbergia odorifera)、3种治理模式(顶果木纯林、降香黄檀纯林、顶果木×降香黄檀混交林)的造林试验,研究不同石漠化治理模式下林分造林成活率、保存率和幼林生长表现及适应机制。[结果]不同树种和不同治理模式林分的造林成活率和保存率存在一定的差异:纯林中,降香黄檀的平均成活率较高(93%~96%),顶果木的较低(81%~87%);混交有利于提高成活率和保存率。不同治理模式林分的平均胸径和平均树高均随着年龄的增加而增加,顶果木纯林的年平均胸径和年平均树高生长量(1.73 cm和1.87 m)显著高于降香黄檀纯林(1.26 cm和1.33 m);混交林中,顶果木的年平均胸径和年平均树高生长量分别是1.81 cm和2.07 m,高于纯林;降香黄檀的年平均胸径和年平均树高生长量相应为1.15 cm和1.39 m,胸径稍低于纯林,而树高稍高于纯林。[结论]顶果木和降香黄檀均能适应石漠化生境,顶果木的生长表现优于降香黄檀,混交可以提高林分的造林成活率、保存率及生长量。

Abstract:

[Objective] The objective of this study was to understand the effects of different combating rock desertification models on afforestation preserving rate and young plantation growth.[Methods] The afforestation experiment with two tree species (Acrocarpus fraxinifolius and Dalbergia odorifera) and three combating rock desertification models (pure A.fraxinifolius plantations, pure D.odorifera plantations and mixed A.fraxinifolius×D.odorifera plantations) was conducted to reveal the afforestation preserving rate, young plantation growth and adaptive mechanism in different combating models.[Results] There were some differences in the survival rate and preserving rate of afforestation in different tree species and combating models. The survival rate of D.odorifera was relatively higher (93%~96%) and that of A.fraxinifolius was relatively lower (81%~87%). Mixed planting could increase survival and preserving rate. Under different combating models, the mean DBH and increment of tree high increased with plantation age. The annual mean DBH and tree height increment (1.73 cm and 1.87 m, respectively) of pure A.fraxinifolius plantations were significantly higher than that of pure D.odorifera plantations (1.26 cm and 1.33 m, respectively).In mixed plantations, the annual mean DBH and tree height increment of A.fraxinifolius were 1.81 cm and 2.07 m respectively, which were higher than that of the pure plantations. However, the annual mean DBH and tree height increment of D.odorifera in mixed plantations were 1.15 cm and 1.39 m respectively. The DBH was slightly lower and tree height was slightly higher than that of the pure plantations.[Conclusion] A.fraxinifolius and D.odorifera could both adapt to rock desertification habitat. The growth of A.fraxinifolius was superior to D.odorifera.Mixed planting with these two tree species could increase afforestation survival rate, preserving rate and growth of the trees.