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本文主要研究了玉龙山亚高山针叶林(3000—3800米)的天然更新。调查分析了坡向、坡度、乔木郁闭度、下木覆盖度、枯枝落叶层厚度与天然更新的关系。2.在不同树种的林冠下,天然更新有其一定的共同规律。同时,由于各树种特性的不同,显示出某些差异。总的来看,乔木郁闭度中等、下木稀疏、缓坡以及枯枝落叶层厚度在5厘米以下,最有利于高山针叶林天然更新。但不同树种要求不同的坡向,云杉宜于阳坡,冷杉宜于阴坡,混交林则宜于半阳坡。3.当高山针叶林被火烧后,原来林内耐荫的植物不见了,迹地上代之而起的是耐早喜光的种类,山杨、桦木和柳逐渐生长起来。在阳性树种的庇荫下,才又有耐荫针叶树种出现,开始漫长的演替过程。4.就玉龙山的调查研究,提出对滇西北高山针叶林的开发意见。该林区应在发挥森林效益的前提下,制订合理的经营方针。
This paper mainly studies the natural regeneration of Yulongshan subalpine coniferous forest (3000-3800 m). The relationship between slope orientation, slope degree, canopy density, understory coverage, litter layer thickness and natural regeneration was investigated and analyzed. 2. Under the canopy of different tree species, natural regeneration has its own common law. At the same time, some differences were shown due to the different characteristics of the species. Overall, the canopy density is moderate, the understory is sparse, the gentle slope and the litter layer thickness is under 5 centimeters, which is most beneficial to the natural regeneration of the coniferous forest. However, different species require different slope, spruce should be sunny, fir suitable for the shady slope, mixed forest is appropriate in the semi-sunny slope. When alpine coniferous forests were burned, shade-resistant plants in the forest disappeared. Species that grew in resistance to early-morning light grew asylum, birch and willow. Under the shade of the positive tree species, there are again shade-tolerant conifer species appear, beginning a long process of succession. 4. Based on the investigation of Yulong Mountain, we put forward the opinions on the development of alpine coniferous forest in northwestern Yunnan. The forest area should exert the forest management benefits under the premise of formulating a reasonable management policy.