A Study on the Growth Analysis of Pinus koraiensis Seedings under Various Relative Light Intensities and Planting Densities

잣나무 묘목(苗木)의 생육환경(生育環境) 요인(要因)에 따른 생장해석적(生長解析的) 연구(硏究)

For the improvement of nursery condition and the study of eco-physiological characteristics of Pinus koraiensis(2-2) seedlings, the primary productivity was investigated and the growth characteristics and their correlationship were analyzed from May to September in 1987. Seedlings used in this study were grown at the nursery of Experimental Forestry of Kyung Hee Univ. The installation of experimental plots were divided into control plot (100%), 63%, 37% and 19% relative light intensity, and each relative light intensity plots were split into $15{\times}15/m^2$, $12{\times}12/m^2$, $9{\times}9/m^2$ and $6{\times}6/m^2$ plnting density by randomized black design method. To take into account the edge effect of plant population, material were selected from each plot by random sampling at 30 days interval. Each sampled material was divided into leaf and stem drived in a drying oven at the temperature of $85^{\circ}C$ until it had constant weight and weighed. and leaf area was surveyed. Growth analysis for RGR and NAR was done by Blackman method and correlation coefficient were investigated between RGR and NAR by analyzing the dry matter production and growth characteristics of the material, cultivated on the experimental nursery under the condition of different treatment the obtained result were as follows : 1. The increasing rate of dry matter was similar at early stage of growth, but not at late stage. 2. Leaf area growth was the maximum value at 63% relative light intensity and the minimum at 19% RLI 3. The value of RGR was the highest on June under $6{\times}6/m^2$ planting density in 63% relative light intensity, the lowest on September under $12{\times}12/m^2$ of 19% relative light intensity. 4. The change NAR decreased in early stage of growth, while it increased on August and September, The value of RGR on June under $6{\times}6/m^2$ planting density in 100 light intensity was the highest, and on September under $12{\times}12/m^2$ planting density in 19% relative light intensity was the lowest. 5. Regression and correlation between RGR and NAR showed significantly positive.

물질생산적(物質生産的) 측면(側面)에서 잣나무에 대한 광환경(光環境) 및 식재밀도(植栽密度)를 달리한 생육조건(生育條件)과 그에 따른 묘목(苗木)의 생장관계(生長關係)를 추적(追跡)하고 생육환경(生育環境)의 개선방안(改善方案)을 위(爲)한 양묘생산(養苗生産)의 기초확립(基礎確立)을 목적(目的)으로 광도(光度) 및 식재밀도(植栽密度)를 각각 4개(個) 수준(水準)으로 구분(區分) 생육(生育)시킨 잣나무 묘목(苗木)(2-2)를 대상으로 영국계(英國系)의 생장해석법(生長解析法)을 도입(導入), 이들에 대한 묘목(苗木)의 상대생장율(相對生長率)(Relative growth rate)과 순동화율(純同化率)(Net assimilation rate) 등을 산출(算出)하였다. 또한 상대생장율(相對生長率)과 순생장율(純生長率) 간(間)의 상관관계(相關關係)를 통계적(統計的)으로 비교(比較) 분석(分析)하였던 바 잣나무 묘목(苗木)의 생육(生育) 환경개선방안(環境改善方案)의 모색이 요구(要求)되었기에 그 결과(結果)를 요약(要約)하면 다음과 같다. 1. 묘목(苗木)의 건중량생장(乾重量生長)의 변화(變化) 양상(樣狀)은 각(各) 처리구간(處理區間) 공(供)히 생육초기(生育初期)에는 큰 차이(差異)가 없었으나 생육후기(生育後期)에는 차이(差異)를 나타냈고 광도(光度)가 높을수록, 그리고 식재밀도(植栽密度)가 소(疎)할 수록 증가(增加)하여 광조건(光條件)의 변화(變化)가 물질생산(物質生産)에 미치는 영향(影響)에 주요(主要)한 변수(變數)로 작용(作用)되었다. 2. 엽면적생장(葉面積生長)은 상대광도(相對光度) 63%구(區)가 가장 컸고, 그보다 광도(光度)가 높거나 낮아질 수록 점차(漸次) 감소(減少)하였다, 상대광도(相對光度) 19%구(區)가 가장 적게 나타났다. 3. 상대생장율(相對生長率)(RGR)은 상대광도(相對光度) 63%구(區)에서 $6{\times}6/m^2$ (36본(本))구(區)의 6월(月) 생장(生長)이 최대(最大)였고, 상대광도(相對光度) 19% 구(區)에서 $12{\times}12/m^2$(224본(本))구(區)의 9월(月) 생장(生長)이 최소치(最少値)를 나타냈다. 4. 순동화율(純同化率)(NAR)은 생육초기(生育初期)에는 감소(減少)하다가 8월(月)과 9월(月)을 기점(起點)으로 증가(增加) 하였으며 상대광도(相對光度) 100%의 $6{\times}6$=36본(本)$/m^2$구(區)에서 6월(月)의 생장(生長)이 최대치(最大値)를, 그리고 상대광도(相對光度) 19%구(區)에서 $12{\times}12$=144본(本)$/m^2$구(區)의 9월(月) 생장(生長)이 최소치(最少値)를 나타냈다. 5. 상대생장율(相對生長率)과 순동화율(純同化率) 간(間)에는 모두 고도(高度)의 유의성(有意性)이 인정(認定) 되었으며 이들은 정(正)의 상관관계(相關關係)에 있었다.