Abstract
According to the concept of woodland aesthetic in Germany and forest design in United Kingdom, artificial forest should be restore ecologically step by step in National Park, Korea. This study was carried out to provide the density criterion of thinning for the inducement of the ecological succession by analysing of vegetational structure in Artificial Forest, National Parks. Eleven plots(size is $20m{\times}20m$) were set up in the artificial forest such as Pinus koraiensis forest, Abies holophylla forest, Chamaecyparis obtusa forest, Populus tomentiglandulosa forest, and Larix kaempferi forest and in the natural forest such as Pinus densiflora community, Pinus densiflora-Quercus serrata community, and Quercus serrata community in Chiaksan, Songnisan, Deogyusan, and Naejangsan National Parks, Korea. We classified the artificial forest into undeveloped type of succession, type of alien young trees developing, and early phase type of succession based on the vegetational structure. According to the index of Shnnon's diversity(unit: $400m^2$), undeveloped type of succession was ranged from 0.9681 to 1.1323, type of alien young trees developing was ranged from 1.0192 to 1.1870, early phase type of succession was ranged from 1.3071 to 1.3892, and natural vegetation was ranged from 1.2202 to 1.3428, therefore early phase type of succession forest and natural vegetation are more higher than simple-layered artificial forest with one needle leaf tree species. The limit for the step-by-step thinning was in the range of 30~60%. In case of undeveloped type of succession, we should thin out from large trees throughout three phases, because alien species dominated high value 88~90% in canopy layer. In case of type of alien young trees developing, we should thin out from alien young trees such as Populus tomentiglandulosa throughout one or two phases, because alien species dominated high value 60~97% and young trees with saplings growing up in understory and shrub layer. In case of early phase type of succession, we should thin out from alien trees that compete with native species throughout one or two phases, because alien species dominated less than value 30%.
독일의 산림미학(숲미학)과 영국의 산림디자인 개념에 따르면 우리나라 국립공원 인공림도 단계별로 생태적 복원이 필요하며, 본 연구는 국립공원 인공림의 식생구조를 분석하여 생태적 천이를 유도하기 위한 식생유형별 간벌 밀도 기준을 제시하고자 수행하였다. 국립공원 중 치악산, 속리산, 덕유산, 내장산에 분포하는 잣나무림, 전나무림, 편백림, 은사시나무림, 일본잎갈나무림 등 인공림 8개소와 소나무군집, 소나무-졸참나무군집, 졸참나무군집 등 자연림 3개소 등 총 11개소에 $20m{\times}20m(400m^2)$ 크기의 방형구를 설정하였다. 식생구조 특성을 고려하여 인공림을 천이미발달형, 외래종치수발달형, 천이초기형으로 유형화하였다. 종다양도(H')는 천이미발달형 0.9681~1.1323, 외래종치수발달형 1.0192~1.1870, 천이초기형 1.3071~1.3892, 자연림 1.2202~1.3428로 침엽수 단일수종 위주의 단층구조의 인공림보다 천이초기형 인공림과 다층구조의 자연림의 종다양도가 다소 높았다. 단계별 간벌 밀도는 30~60% 범위로 하되, 천이미발달형은 외래종 우점치가 88~90%로 높으므로 대경목부터 3단계에 걸쳐 간벌하고, 외래종치수발달형은 외래종 우점치가 60~97%로 높고 아교목층과 관목층에 치수가 발달하고 있어 조기에 외래종 치수를 제거하고 1단계 또는 2단계에 걸쳐 간벌하며, 천이초기형은 외래종 우점도가 30% 이하로 자생종과 경쟁하는 외래종을 우선적으로 간벌하고 1단계 또는 2단계에 걸쳐 간벌할 것을 제시하였다.
