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This study aimed to investigate the effect of suppressing transpiration on the physiological characteristics of trees and identify suitable indicators to assess tree vitality. Three seedlings of Zelkova serrata were used: a control, a unit treated on the upper sides of the leaves (TU), and a unit treated on double sides of the leaves (TD). Changes in photosynthetic rate, transpiration rate, sap velocity, and bark temperature following the suppression of transpiration were measured. The transpiration rate and other physiological characteristics of TU were not significantly different from those of the control except for photosynthetic rate. However, TD showed a significantly lower photosynthetic rate, transpiration rate, and sap velocity compared to the control. The bark temperature of TD was not significantly higher than that of the control and TU. Our findings indicate that photosynthetic rate and sap velocity were positively correlated with transpiration rate, whereas bark temperature was negatively correlated. Furthermore, photosynthetic rate showed the most significant linear relationship with transpiration rate, suggesting the photosynthetic rate is a suitable physiological indicator to evaluate the vitality of Z. serrata.

Background The stem exclusion stage is a stage of forest development that is important for understanding the subsequent understory reinitiation stage and maturation stage during which horizontal heterogeneity is formed. Over the past 11 years (2009–2019), we observed a deciduous broad-leaved forest in the Albongbunji Basin in Ulleungdo, South Korea in its stem exclusion stage, where Fagus engleriana (Engler’s beech) is the dominant species, thereby analyzing the changes in the structure (density and size distributions), function (biomass and species richness), and demographics. Results The mean stem density data presented a bell-shaped curve with initially increasing, peaking, and subsequently decreasing trends in stem density over time, and the mean biomass data showed a sigmoidal pattern indicating that the rate of biomass accumulation slowed over time. Changes in the density and biomass of Fagus engleriana showed a similar trend to the changes in density and biomass at the community level, which is indicative of the strong influence of this species on the changing patterns of forest structure and function. Around 2015, a shift between recruitment and mortality rates was observed. Deterministic processes were the predominant cause of tree mortality in our study; however, soil deposition that began in 2017 in some of the quadrats resulted in an increase in the contribution of stochastic processes (15% in 2019) to tree mortality. The development of horizontal heterogeneity was observed in forest gaps. Conclusions Our observations showed a dramatic shift between the recruitment and mortality rates in the stem exclusion stage, and that disturbance increases the uncertainty in forest development increases. The minor changes in species composition are likely linked to regional species pool and the limited role of the life-history strategy of species such as shade tolerance and habitat affinity. Our midterm records of ecological succession exhibited detailed demographic dynamics and contributed to the improvement of an ecological perspective in the stem exclusion stage.

A giant dogwood (Cornus controversa) was bleeding transparent sap that turned into gummy orange slime with a pungent odor on the bark in early April. The tree exudation originated from a branch wound that occurred during the most recent spring pruning. Scanning electron microscopy revealed the intact bark surface was irregularly undulating and covered with at least three types of epicuticular waxes: polygonal rodlets; polygonal tubules; and threads, whereas the dried orange plaques were covered with fungi, possibly the co-occurrence of yeast and filamentous forms. The yeast forms were ovoid, lemon- or club-shaped, and approximately 10 μm in length. Obviously constricted septa and clamp connections were rarely detected on the filamentous forms. No bacterial proliferation was detected on the orange slime. X-ray microanalysis revealed a steep increase in calcium concentration in the orange plaques compared with that in the intact bark. These results suggest that bark-dwelling dimorphic red yeasts may...

Additional file 1: Supplementary Figure S1. The frequency distribution histograms of the diameter class (top) and biomass class (bottom) measured in the tree communities in the Albongbunji Basin over a period of 11 years.

Additional file 2: Plate 1. The survey plot was installed in Albongbunji Basin, Ulleungdo, taken in 2019 (left). This young beech forest (approximately 60 years old) is in the stem exclusion stage of forest development. Broken stems of the canopy species Prunus takesimensis (Ulleungdo cherry, endemic species) and Acer pictum var. mono originated from gap events induced by stochastic disturbances (wind and mechanical damage), which were observed at an earlier stage than in traditional development models. The forest floor of the survey plot is continuously changing in terms of micro-level geomorphology due to soil deposition caused by heavy rains. In part of the survey plot, soil deposition has been taking place since 2016 (right). The red arrow on the picture is the spot where the number tag was attached at the breast height (120 cm) in 2009.

천연기념물 제 432호 제주 상효동의 한란 자생지(39 ha)를 대상으로 2013년 10월부터 2014년 2월까지 생물(식물상, 식생다양성 및 임분 구조) 및 비생물 환경(미기상, 수관열림도, 임내 광량 및 토양 온 습도)의 특성을 분석하였다. 한란 자생지의 일평균온도( $5.7^{\circ}C$ )는 서귀포시 보다 $3.3^{\circ}C$ 낮았고...

Based on the specimens of Tortricidae collected from North Korea by Hungarian Natural History Museum, totally twelve species were identified. Among them, two species, Notocelia rosaecolana Doubleday and Rhopobota ustomaculana Curtis, are reported for the first time from North Korea. All identified species is enumerated with their available information including the collecting localities, the distributional ranges and host plants.

In this study, we impregnated nanometal samples having various concentrations 0, 1000, 3000, and 5000 ppm in biomass in order to make carbonized biomass. We analyzed the properties of the impregnated samples through thermogravimetry/differential thermal analysis (TG–DTA), iodine adsorptivity, fixed carbon ratio, pore distribution, scanning electron microscopy (SEM), and transmission electron microscopy (TEM). The best results were observed for a nanometal concentration of 5000 ppm. After the first heat treatment, carbonization, and activation processes, the fixed carbon ratio and iodine adsorptivity were increased by 11.07% and 42 mg/g, 11.07% and 198 mg/g, and 46.7% and 1185 mg/g, respectively. Through repeated experiments, we established the most effective process for impregnating a nanometal in biomass.

Pinus thunbergii plantations in Pohang-si, Gyeongsangbuk-do, Korea, are of low ecological quality, with arrested succession and a high proportion of ruderal species. To improve the quality of the habitat, we created canopy gaps () and monitored changes in abiotic (light availability, canopy openness) and biotic (survival and growth of seedlings and understory communities) variables in 2007 and 2008 in plots that had received one of five types of treatment: cutting of canopy trees and removal of the understory (CU), cutting of canopy trees only (C), girdling of canopy trees and removal of the understory (GU), girdling of canopy trees (G) or control. Each treatment was applied to three replicate plots. Abiotic variables did not significantly differ among treatments. Survival rates of target species were slightly lower in the CU, G and control conditions. Based on logistic regression analysis, the only significant growth factor affecting survival was height growth. Positive effects of seedling height and leaf area growth on survival were also detected, but did not reach statistical significance. In treatment G, gradual improvement of overstory conditions and mitigation of competition by limitation of disturbance to the understory community were likely to have promoted seedling growth. There were no significant effects of gap treatments on changes in species abundance (cover and richness) and composition of understory between the study years. This result implies that the small gaps created in our study may be below the threshold size to affect understory growth. However, the results of this study are based on a short-term investigation of only two years. Long-term research is strongly recommended to clarify the effects of gap treatment on plant communities in afforested areas.

Forest vegetation types and growth characteristics of Seongin-bong at Ulleung Island in Korea were studied by using importance values, distributions of diameter classes, and annual growth analysis. Vegetation types were classified into 7 groups. The number of existing woody plant and herbaceous plant species varied from 17 to 21 species per . In case of life-forms importance values, woody and herbs showed average values of 47% and 53% across 5 groups. But in Tsuga sieboldii-Pinus parviflora and Fague engleriana- Taxus cuspidata var. latifolia groups, woody importance values were 68% and 54%, respectively. Diameter classes in most stand types were regularly distributed and showed continuous growth in annual diameter growth. from these results, this site is expected to maintain a stable vegetation structure continuously. F. engleriana, which forms major species in this site, showed 0.46-0.62 cm in annual average diameter growth. The annual average diameter growth of broad-leaved tree species was 0.2-0.6 cm, while the growth rate of T. sieboldii and P. parviflora was 0.38 cm and that of T. cuspidata var, latifolia was below 0.1 cm.

We assessed the species composition and structure of the three representative forest stands(Pinus densiflora stand, Quercus variabilis stand, and Ouercus mongolica stand), dominated in the National Long-Term Ecological Research Sites of Mt. Worak, Korea and established a benchmark series of permanent plots and transects with which future changes in forest composition and structure could be monitored. Species richness of Q. mongolica stand was greater than other two stands, due in large part to the greater habitat heterogeneity. Number of trees and species are decreased with increasing DBH classes. The successional trends of the three study stands would be mostly changed as Q. mongolica forest, regardless of forest types. Mean density ratio between alive trees and dead trees of three forest stands appeared with Q. mongolica stand 75:25, Q. variabilis stand 94:6, and P. densiflora stand 86:14, Q. mongolica stand appeared most highly from in three stands. This may be due to interspecific or intraspecific competition that it follows in various successesional stages. One side, when it saw the tree status which shows the tree health, the three forest stands all standing alive type (AS) appeared most highly with 75% to 85% and fallen dead type (DF) did not appear entirely. Remeasurement of permanent plots at periodic intervals will provide useful information on the dynamics of the forest vegetation that can be used in the development of adaptive conservation plans.

Today smartphone is expected to play a key role in the fast growing LBS market. Many studies have been carried out to develop the LBS service on the smartphone and to evaluate the service quality of the smartphone based location service. However, most of studies focused on the positioning performance not at the urban canyon that is one of the major service target areas but at the general environment. In this paper, we developed a mobile application to test the performance of Android location service and to collect the positioning results as well. We also carried out some experiments to evaluate the quality of the location service and the reliability of GPS and WPS at a dense urban area.