飞播马尾松林的抚育间伐研究

对飞播马尾松林抚育间伐的试验研究表明:间伐与不间代相比,其胸径和树高生长量均有增加。间伐后立木保存密度为3300株/hm~2,4050株/hm~2,4800株/hm~2和5550株/hm~2的4a胸径增长率分别为3.43％,2.85％,2.64％和2.56％,分别为不间伐的249.00％,207.00％,191.00％和180.00％;4a树高增长率分别为2.24％,1.90％,1.75％和1.75％,分别为不间伐的149.00％,127.00％,117.00％和117.00％。经抚育间伐的马尾松林分,林木生长中等以上的株数平均占65.00％以上;不间伐的林分,林木生长中等以上的株数仅占30.00％左右。在立地条件较好的情况下,间伐后立木保存密度3000～3750株/hm~2为宜。

On Improvement Cutting of Aerial Sowing Masson's Pineta

The measurements of 4 years after improvement cutting proved that masson's pineta increments of DBH and tree height both became larger than before. The increment percentages of DBH for stand densities 3 300, 4050,4800 and 5550 trees per hectare were 3.43%, 2.85%, 2.64% and 2.56% respectively, with contrasts of 240.00%, 207.00%, 191.00% and 186.00% respectively. The increment percentages of tree height were 2.24%, 1.90%, 1.75% and 1.75% respectively, with contrasts of 149.00%, 127.00%, 117.00% and 117.00% respectively. The amount of middle growing made up 65.00% and over in the improvement cutting stands, but only 30.00% or so in the contrast stands. Stand densities of 3 000 to 3 750 trees per hectare were appropriate in the plots of good quality class.