岩溶石漠化不同修复林分的早期生长动态分析

Early Growth Dynamic Analysis of Different Restoration Stands in Karst Rocky Desertification

关键词:  石漠化  纯林  混交林  胸径  树高  蓄积量  生长动态

Key words:  rocky desertification  pure plantation  mixed plantation  DBH  tree height  volume  growth dynamic

摘要:

为阐明岩溶石漠化不同修复林分的早期生长动态特征及变化规律，选择2011年营造的顶果木(Acrocarpus fraxinifolius)纯林(PAFP)、降香黄檀(Dalbergia odorifera)纯林(PDOP)和顶果木×降香黄檀混交林(MADP)为研究对象，设置固定监测样地，基于2013年、2015年、2019年、2021年的4次林分调查，研究了3种修复林分胸径、树高、蓄积量的动态变化。结果表明，监测期8 a内，3种修复林分平均胸径、树高和林分蓄积量均随时间推移显著增加；PAFP林分蓄积量增长率为137.23%，MADP为292.28%，PDOP为1 090.39%；3种林分单株胸径、树高和蓄积量年平均生长量均表现为PDOP (0.76 cm，0.56 m，0.004 m³)>MADP (0.55 cm,0.53 m，0.003 m³)>PAFP (0.34 cm，0.30 m，0.002 m³),3种林分蓄积量年平均生长量也表现为PDOP (5.49 m³/hm²)> MADP (4.50 m³/hm²)> PAFP (3.01 m³/hm²),3种林分间差异显著；3种林分的平均胸径与树高存在极显著的正相关关系(P<0.001)，顶果木与降香黄檀混交可以促进顶果木的胸径和树高生长，同时也能促进降香黄檀的树高生长。这一结果表明混交有利于促进顶果木和降香黄檀的生长，减缓顶果木的生长衰退。

Abstract:

In order to clarify the growth dynamic characteristics and variation rules of different restoration stands in Karst rocky desertification, the pure Acrocarpus fraxinifolius plantation (PAFP), pure Dalbergia odorifera plantation (PDOP), mixed A.fraxinifolius and D.odorifera plantation (MADP) constructed in 2011 were selected as the research objects.Based on four continuous stand survey in 2013, 2015, 2019 and 2021, respectively, the dynamic changes of DBH, tree height and stand volume of three restoration stands were studied by setting a fixed monitoring sample plot.The results showed that within 8 years of monitoring period, the average DBH, tree height and stand volume of the three restoration stands have been increased significantly with time.The growth rate of stand volume in PAFP, MADP and PDOP were 137.23%, 292.28% and 1 090.39%, respectively.The average annual increments of DBH, tree height and volume for an individual tree of the three stands were PDOP (0.76 cm, 0.56 m, 0.004 m³)>MADP (0.55 cm, 0.53 m, 0.003 m³)>PAFP (0.34 cm, 0.30m, 0.002 m³). The average annual increment of stand volume of the three stands showed the same trend, i.e.PDOP (5.49 m³/hm²)>MADP (4.50 m³/hm²)>PAFP (3.01 m³/hm²).There were significant different among the three stands.There was an extremely significant positive correlation between the average DBH and tree height of the three restoration stands.The mixing of A.fraxinifolius and D.odorifera promoted the growth of DBH and tree height of A.fraxinifolius, and accelerated tree height growth of D.odorifera. The results have proved that the mixing is beneficial to help the growth of both A.fraxinifolius and D.odorifera, and mitigate the growth decline of A.fraxinifolius.