The active compounds of medicinal plants vary in composition and content depending on environmental factors, such as light, temperature, and soil. According to the Korean Pharmacopoeia standards for herbal medicine, the sum of nodakenin, decursin, and decursinolangelate, which are the marker components of Korean Angelica, should be at least 6.0 g/100 g. However, the content of the components in Korean Angelica cultivated in South Korea often fall below 6.0 g/100 g, due to weather conditions and cultivation site characteristics. This study aimed to gather information about environmental factors that affect the root growth and the content of active compounds. In total, 18 cultivation sites in Pyeongchang, Jecheon, and Bonghwa regions in Korea were investigated for this study. Environmental factors, such as the monthly mean temperature, mean relative humidity, duration of sunshine, total precipitation, soil acidity, and the characteristics of soil nutrient, were investigated over the growing season from April to October 2017. As for the growth characteristics, the dry weight of roots of Korean Angelica was measured. The sum of the contents of the three active compounds was 5.3–7.0 g/100 g and the nodakenin content was 0.3–1.3 g/100 g in the cultivation sites. This study concludes that the root yields in the cultivation sites would be improved if weather conditions are maintained with similar levels as those in their natural habitats. Additionally, the environment that improves root growth did not increase the content of active compounds; however, when there was a lot of gravel or high temperatures during the growth period, the content of active compounds was relatively high.

The Siberian elm (Ulmus pumila L.) is one of the most commonly found tree species in arid areas of northeast Asia. To understand the morphological and physiological characteristics of Siberian elms in arid regions, we analyzed leaves from seven study sites (five arid or semi-arid and two mesic) in China, Mongolia and the Republic of Korea, which covered a wide range of average annual precipitation (232 mm·year⁻¹ to 1304 mm·year⁻¹) under various aridity indexes (AI) and four different microenvironments: sand dune, steppe, riverside and forest. The traits of Siberian elms varied widely along different annual precipitation (P) and AI gradients. Tree height (H), leaf size (LS) and stomatal area per unit leaf area (A_S/A_L) decreased with increasing AI, whereas leaf mass per unit leaf area (LMA) and water-use efficiency (WUE) increased significantly. In addition, trees at the five arid sites showed significant differences in LS, LMA and A_S/A_L but not in H and WUE. Thus, our study indicated that indigenous Siberian elm trees in arid areas have substantially altered their morphological and physiological characteristics to avoid heat stress and increase water conservation in comparison to mesic areas. However, their changes differed depending on the surrounding microenvironment even in arid areas. Trees in sand dunes had a smaller LS, higher LMA, thicker leaf cuticle layer and higher stomatal density and A_S than those in steppes and near a riverside.

Mangroves are adapted to coastal processes; however, mangrove species showed various responses to estuarian environments, leading to different structural characteristics at accretion and erosion areas. The species composition, structure and regeneration of mangrove forests were investigated to provide insight into mangrove forest development in response to shoreline accretion and erosion processes. The species composition and stand structure of mangrove forests were measured along the distance from the shoreline at accretion and erosion sites in Ca Mau, Vietnam. The hierarchical clustering of grouped stands based on species composition and tree size distribution was conducted. Grouped mangrove stands showed landward changes in species composition and stand structure from the shoreline (p < 0.05), reflecting the timescale of accretion or erosion at both accretion and erosion sites. Stand development patterns differed between accretion and erosion sites, and Avicennia alba and Rhizophora apiculata dominated seaward plots at accretion and erosion sites, respectively. Newer accredited sites were dominated by A. alba. Mangrove stands developed from dense A. alba dominant to R. apiculata dominant stands with increasing tree size at accretion sites. There were more species-colonized sites with a higher erosion rate or that were more recently eroded, implying that timescale of erosion and erosion rate affected species composition and regeneration on erosion sites. Accretion and erosion affected stand development of mangroves differently, implying that conservation and restoration strategies should be applied differently to accretion and erosion sites.

Distinct seasons and diverse tree species characterize temperate deciduous forests in NE Asia, but large areas of deciduous forests have been converted to conifer plantations. This study was conducted to understand the effects of seasons and tree species on leaf litter decomposition in a temperate forest. Using the litterbag method, the decomposition rate and nitrogen, phosphorous, and carbon dynamics of Mongolian oak (Quercus mongolica), Korean pine (Pinus koraiensis), and their mixed leaf litter were compared for 24 months in a Mongolian oak stand, an adjacent Korean pine plantation, and a Mongolian oak—Korean pine mixed stand. The decomposition rates of all the leaf litter types followed a pattern of distinct seasonal changes: most leaf litter decomposition occurred during the summer. Tree species was less influential on the leaf litter decomposition. The decomposition rates among different leaf litter types within the same stand were not significantly different, indicating no mixed litter effect. The immobilization of leaf litter N and P lasted for 14 months. Mongolian oak leaf litter and Korean pine leaf litter showed different N and P contents and dynamics during the decomposition, and soil P₂O₅ was highest in the Korean pine plantation, suggesting effects of plantation on soil nutrient budget.