Stemflow (SF) is essential for water resources within forest ecosystems and can constitute up to half of the gross rainfall (GR), depending on the forest stand structures in coniferous plantations. Although numerous studies on SF yield have been reported globally for various forest types, very few studies on SF have been reported to examine the influence of forest stand structures on SF in Korea. This study aimed to quantify the relationship between SF and forest stand structures in unmanaged Japanese cypress plantations. Two study plots were established (10 m × 10 m each) in plantations with the same stem density (SD: 2500 stems ha-1) (hereafter P1 and P2). Almost all forest stand structures (canopy projection area, tree height, diameter at breast height (DBH), number of live and dead branches, and ratio of canopy length to canopy width), including canopy volume using mobile LiDAR devices, were investigated. To evaluate the efficiency of funneling rainwater for the effect of tree biomass on SF, a funneling ratio (FR) was used. The present SF ratios (20.7% in P1 and 22.3% in P2) were much higher than those reported in previous studies of various forest types in Korea (SF ratios: 0.2–5.8% with a mean of 2.0%). This is due to the interaction between the high SD and many under-canopy dead branches. Individual-scale FR was correlated with DBH (R2 = 0.43). The present stand-scale FRs (FRstand) (22.3 in P1 and 29.2 in P2) were much higher than those reported in the previous studies (FRstand: 1.0–33.3 with a mean of 7.8) because of the negative relationship between FRstand and mean DBH (R2 = 0.78, p = 0.02). Our results provide useful information for understanding changes in SF caused by forest stand structures.
Throughfall (TF)—as a diffusive hydrological water flux—significantly affects ecohydrological and biogeochemical processes within forest ecosystems. Recent investigations have revealed the impact on TF generation processes within unmanaged coniferous plantations of under-canopy structures, particularly those laden with dead branches, as well as upper-canopy structures. However, spatiotemporal variations in TF in such plantations remain unexplored. We investigated these variations in TF in a 33-year-old unmanaged Japanese cypress (Chamaecyparis obtusa Endl.) plantation, laden with dead branches, with a high stand density (SD) of 2,500 stems ha−1. Over a two-year period (May 2017 to May 2019), we conducted weekly TF measurements using 28 manual-type TF collectors. We compared the present TF ratio and canopy water storage capacity (S) with those of previous investigations conducted on Japanese cypress plantations. Moreover, we assessed key indices contributing to spatiotemporal TF variations (canopy cover: CC and distance to the nearest stem: TFd) and potentially influential dead branch indices (number of dead branches: TFdb and vertical spacing length on a stem: TFs) to elucidate TF spatial patterns. The results showed that the TF ratio was notably lower than that in previous studies (n = 13), with SD (r = –0.92, p < 0.001) and S (r = –0.87, p < 0.001) emerging as key influential factors among other stand-structure parameters. Spatial TF patterns exhibited a decreasing trend as the gross rainfall (GR) increased. Temporal stability was not significantly associated with CC (r = 0.120, p = 0.544), TFd (r = 0.068, p = 0.731), TFdb (r = 0.211, p = 0.281), or TFs (r = 0.206, p = 0.292) for any of the TF collectors. These findings underscore the important role of GR in determining the spatial variation of TF. Collectively, our results contribute to an enhanced understanding of TF spatiotemporal heterogeneity in unmanaged Japanese cypress plantations with dead branches.
본 연구는 경상남도 함양군 대봉산의 산림휴양단지 조성예정지의 식물상을 분석, 보존 및 보호방안을 수립하기 위하여 2015년 4월부터 10월까지 수행되었다. 전체적인 식물상은 80과 172속 212종 3아종 26 변종 5품종으로 총 246분류군이 확인되었고, 양치식물계수는 0.71로 분석되었다. 과별 분포현황은 국화 과, 백합과, 장미과, 벼과 순으로 높게 나타났고, 종/속 비율은 1.23으로 나타났다. 특산식물은 은꿩의 다리, 노각나무, 흰괭이눈, 고광나무, 병꽃나무 등 총 5분류군이 나타났고, 희귀식물은 측백나무, 태백 제비꽃, 말나리, 꽃창포 등 총 4분류군이 나타났다. 귀화식물은 애기수영, 미국자리공 등 총 12분류군 으로 귀화율은 4.9%였다. 식물구계학적 특정식물은 총 20분류군으로써, Ⅳ등급 측백나무, 고로쇠나무 등 총 2분류군, Ⅲ등급 흰진범, 노각나무 등 총 3분류군, Ⅱ등급 털괭이눈, 돌양지꽃 등 총 6분류군, Ⅰ등급 개비자나무, 물박달나무 등 총 9분류군이 나타났다. 본 연구에서 도출한 결과를 이용하여 조성 예정지의 생태정보를 제공함과 동시에 보전과 활용방안 수립을 위한 기초자료로 활용할 수 있을것이다.
This study was carried out to provide the basic informations on the sustainable management methods for soil resources by determining the soil physico-chemical properties of specialized plant gardens (Sedum garden, Fern garden, Medicinal plant garden, Ornament plant garden, Rare & endemic plant garden, and Shrub garden) and forest in Korea National Arboretum. Soil particle size showed similar distribution except for Sedum garden and Medicinal plant garden. Soil bulk densities were significantly difference among forest and specialized plant garden (p<0.05) and ranged from 0.79 g/cm 3 in Sedum garden to 1.13 g/cm 3 in shrub garden. Sedum garden and medicinal plant garden showed significantly low of soil moisture content (p<0.05). Soil pH ranged from 4.87 in Sedum garden to 5.41 in rare & endemic plant garden. Soil organic matter content ranged from 2.61% in Sedum garden to 4.71% in forest. The lower value in total N content was 0.11% in Sedum garden and 0.18% in medicinal plant garden. Available phosphorus was significantly lower in Sedum garden and medicinal plant garden than in other specialized plant garden of ranging from 16.90 ppm to 20.34 ppm (p<0.05). The contents of inorganic NH4 + and NO3 - were significantly different among the specialized plant gardens (p<0.05). The ratios of NO3 - to total inorganic N content ranged from 28% in Sedum garden to 44% in fern garden and forest. N mineralization and nitrification rate were also significantly different among the specialized plant gardens (p<0.05).
This study was conducted to provide the basic information for effective conservation and management of coastal forest by analysis the vascular plant in Daewangam park. The vascular plant in Daewangam park was 204 taxa, 73 families, 156 genera, 183 species, 2 subspecies, 4 forma, and 15 varieta. Among them, seashore plants accounted for 6.4% of total plants and they were 13 taxa such as Andropogon ischaemum and Tetragonia tetragonoides, and the Pteridophyte index (Pte-Q) was 0.49. The plants of Compositae, Rosaceae, Graminea, Leguminosae, and Liliaceae showed high distribution. Korean endemic species were 3 taxa such Campanula takesimana, Aster koraiensis and Forsythia koreana. Three rare species of Campanula takesimana, Magnolia kobus and Glehnia littoralis listed as rare plants by the Korea National Arboretum were found in Daewangam park. Naturalized plants were identified 18 taxa including Cerastium glomeratum, Bidens frondosa, and so on, and Naturalization index was 8.8%. The specific species of I~V grades by phytogeography were 28 taxa including Campanula takesimana, Magnolia kobus, Rubus ribisoideus, and so on.