Air pollution and climate change amplify the urban heat island (UHI) effect, which has an adverse effect on human health. Urban forests (UFs) are important to reduce the UHI effect; however, the quantitative effect of UFs on UHI, relative to time and space, has not yet been investigated. In this study, we aimed to quantitatively measure the actual thermal environment in UFs. To this end, temperature and humidity loggers were installed in 17 UFs in Seoul for a year and analyzed according to vegetation characteristics and accessibility. The urban forests and park showed consistent temperature reduction, whereas the lawn showed higher temperature reduction effects during autumn-winter. The traffic island showed lower annual temperature reduction effect than other UFs. From spring to autumn, mixed and broadleaved forests showed better temperature reduction effect than coniferous forests. The temperature in UFs decreased by approximately 1.9°C over ~3 km from the traffic island near the city to the forest. This study revealed the difference in the cooling effect according to the type and location of UF and the vegetation structure. The functional characteristics of plants and the UF that reflects them can help reduce the negative impact of climate warming and UHI on human health.

Recent studies based on morphological characteristics and molecular analyses have revealed that the characteristics of Sparassis crispa from Asia are not concordant with those of collections from Europe and North America. Consequently, the Asian isolate was redefined as Sparassis latifolia. This study is the first report of Sparassis latifolia collected in Korea. The taxonomic relationships and replacement of Sparassis species were inferred from a comparison of the morphological characteristics and by molecular sequence analysis of the internal transcribed spacer (ITS) rDNA regions. In particular, this study focused on the phylogenetic relationships inferred from the biogeographical distribution of isolates within the genus Sparassis.

Some plant species develop aerenchyma to avoid anaerobic environments. InSyzygium kunstleri(King) Bahadur & R. C. Gaur, both primary and secondary aerenchyma were observed in adventitious roots under hypoxic conditions. We clarified the function of and relationship between primary and secondary aerenchyma. To understand the function of primary and secondary aerenchyma in adventitious roots, we measured changes in primary and secondary aerenchyma partial pressure of oxygen (pO₂) after injecting nitrogen (N₂) into the stem 0–3 cm above the water surface using Clark-type oxygen microelectrodes. Following N₂injection, a decrease in pO₂was observed in the primary aerenchyma, secondary aerenchyma, and rhizosphere. Oxygen concentration in the primary aerenchyma, secondary aerenchyma, and rhizosphere also decreased after the secondary aerenchyma was removed from near the root base. The primary and secondary aerenchyma are involved in oxygen transport, and in adventitious roots, they participate in the longitudinal movement of oxygen from the root base to root tip. As cortex collapse occurs from secondary growth, the secondary aerenchyma may support or replace the primary aerenchyma as the main oxygen transport system under hypoxic conditions.

Three new species of Crinipellis (Basidiomycota, Marasmiaceae), and one new variety of Moniliophthora are described from the Republic of Korea. Crinipellis birhizomorpha is characterized as having a short stipe arising from both substrate and rhizomorphs, and as forming rhizomorphs of two types, one forming abortive pilei; C. pallidipilus has golden brown, then distinctly pallescent pileus hairs, very long, hairy rhizomorphs of one type, and rather wide basidiospores in comparison with other species described here; and C. wandoensis has a brown to dark brown pileus, hairy rhizomorphs of one type, and both non-dextrinoid and slightly dextrinoid basidiospores. A new combination, Moniliophthora conchata is proposed. A new variety, Moniliophthora conchata var. brevispora differs from the type variety in having smaller basidiospores. Their detailed macro- and microscopic descriptions are given, and their taxonomic positions were confirmed using DNA studies. A key to the identification of Crinipellis and Moniliophthora taxa recorded in this country is also provided.

Invasive plants have spread across the urban forests in South Korea, resulting in several harmful effects. Socioeconomic aspects of urban environments make urban forests susceptible to invasion. The invasion resistance of the environment is determined by various factors, including native species richness and forest structure; however, this relationship is relatively understudied in urban forests. In this study, we investigated the relationships between invasive plant species richness and different variables, including urban forest structure, native species diversity, and vegetation communities in the urban forests of South Korea, Busan. We investigated these relationships using a stepwise generalized linear model (GLM) and random forest (RF) methods. We used the TWINSPAN method to classify the vegetation communities, and non-metric multidimensional scaling (NMDS) ordination to determine whether certain vegetation communities were prone to invasion. The results showed a weak positive correlation with 0.09 R² value between the richness of invasive species and native Margalef species richness. Native Margalef species richness was also the most important variable showing positive relationship in both GLM and RF. Proximity to human disturbances increased the richness of invasive species, but forest structure had little influence. Ordination showed that no certain community type was susceptible to invasion. These results were due to the afforestation history of the study area and the shade-tolerant characteristics of the invasive species. Because urban forests in South Korea are under increasing environmental stresses, a persistent invasion is expected in the future and require management strategies to maintain the ecosystem services.

Cauliflower mushroom (Sparassis latifolia or S. crispa) is popular for food and medicine. Importance of new varieties of Sparassis was raised and studied widely by protection system of UPOV. In this study, 10 crossbred strains of Sparassis latifolia that specifically expressed distinctive features during basidiocarp formation and mycelium growth were applied to sawdust medium inoculated with S. latifolia mycelia. The 10 crossbred strains were divided into 3 groups on the basis of morphological (size of marginal wave and basidiocarp color) and genetic characteristics. Each phenotype of the parent and crossbred strains represented 3 marginal wave-sizes (large, medium, and small) and 3 color notations (NN155D, 163C, and 8D). Our result suggests that morphological characteristics of cauliflower mushroom can be affected by various environmental and genetic stimuli under artificial conditions such as crossbreed. Also this research showed genetic differences among breeding isolates and their morphological characteristics were correlated with the molecular data within parent and crossed strain.