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在当代林学理论与实践中,十分强调树种的综合评定和系统方法;这对林木遗传与选种、林木良种繁育、引种和造林尤为重要。 在森林的活动中,气候、土壤、地形、地质结构组成,常常影响森林的形成、森林的生产力和森林的质量。同时,树种的生物学特性,树种彼此间及它们与周围环境条件存在着复杂关系。但不能忽视人为因素以及对相应的生长条件和森林类型营建高产林分起主导作用的经济因素。 每个被定名的种群不必划分成更小的构成单位,因为这些种群群体能够总体有机地反映出对树木生长发育的影响。同样,通过人为活动也能改变有关的周围环境条件,但最终起决定作用的还是树木本身的生物学特性。因此,为了提高林分生产力,改善林分的质量成分,应该采用综合方法研究森林的生命、生长发育和生长规律。 目前在评定某个或另一个森林树种或树木,或评定种子繁育场的无性系时,已不满足于只了解1～2种性状,如树高和胸径。通过林业生产实践和科学研究可知,在林木选种、良种繁育,引种和造林时,除了用已规定的指标评定外,还广泛用树木地上部分和地下部份的生物量(气干或绝对干重),主根和针叶的长度,树冠的结构和冠
In the contemporary theory and practice of forestry, great emphasis is placed on the comprehensive assessment of tree species and systematic methods; this is particularly important for forest genetics and seed selection, tree seed breeding, introduction and afforestation. In the activities of forests, the composition of climate, soil, topography and geological structure often affect the formation of forests, the productivity of forests and the quality of forests. At the same time, there is a complex relationship between the biological characteristics of tree species, the species of tree species and their environmental conditions. However, human factors and the economic factors that play a leading role in establishing high-yield stands for the corresponding growth conditions and forest types can not be ignored. Each named population does not have to be subdivided into smaller constituent units because these population groups can overall and organically reflect the impact on tree growth and development. Similarly, the human activities can also change the relevant environmental conditions, but ultimately play a decisive role or the biological characteristics of the trees themselves. Therefore, in order to improve the productivity of stand and improve the quality of stand, we should adopt an integrated approach to study the life, growth and growth of the forest. At present, when assessing one or another forest species or trees, or assessing clones of seed breeding sites, they are no longer satisfied with understanding only one or two traits, such as tree height and breast diameter. Through forestry production practices and scientific research shows that in the forest selection, breeding, introduction and afforestation, in addition to the use of indicators have been provided in addition to the assessment, but also widely used aboveground biomass and underground biomass (air-dried or absolutely dry Heavy), the length of the main root and the needles, the structure and crown of the crown