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We evaluated surface-based analysis for assessing the possible relationship between the microstructural properties and particulate matter (i.e., two size fractions of PM2.5 and PM10) adsorption efficiencies of their leaf surfaces on ten woody species. We focused on the effect of PM adsorption capacity between micro-morphological features on leaf surfaces using a scanning electron microscope and a non-contact surface profiler as an example. The species with higher adsorption of PM10 on leaf surfaces were Korean boxwood (Buxus koreana Nakai ex Chung &amp, al.) and evergreen spindle (Euonymus japonicus Thunb.), followed by yulan magnolia (Magnolia denudata Desr.), Japanese yew (Taxus cuspidata Siebold &amp, Zucc.), Japanese horse chestnut (Aesculus turbinata Blume), retusa fringetree (Chionanthus retusus Lindl. &amp, Paxton), maidenhair tree (Ginkgo biloba L.), and royal azalea (Rhododendron schlippenbachii Maxim.). There was a higher capacity for the adsorption of PM2.5 on the leaf surfaces of B. koreana and T. cuspidata, followed by A. turbinata, C. retusus, E. japonicus, G. biloba, and M. denudata. In wax layer tests, T. cuspidata, A. turbinata, R. schlippenbachii, and C. retusus showed a statistically higher PM2.5 capturing capacity than the other species. Different types of trichomes were distributed on the adaxial and abaxial leaves of A. turbinata, C. retusus, M. denudata, pagoda tree (Styphnolobium japonicum (L.) Schott), B. koreana, and R. schlippenbachii, however, these trichomes were absent on both sides of the leaves of G. biloba, tuliptree (Liriodendron tulipifera L.), E. japonicus, and T. cuspidata. Importantly, leaf surfaces of G. biloba and S. japonicum with dense or thick epicuticular leaf waxes and deeper roughness revealed lower PM adsorption. Based on the overall performance of airborne PM capture efficiency, evergreen species such as B. koreana, T. cuspidata, and E. japonicus showed the best results, whereas S. japonicum and L. tulipifera had the lowest capture. In particular, evergreen shrub species showed higher PM2.5 depositions inside the inner wall of stomata or the periphery of guard cells. Therefore, in leaf microstructural factors, stomatal size may be related to notably high PM2.5 holding capacities on leaf surfaces, but stomatal density, trichome density, and roughness had a limited effect on PM adsorption. Finally, our findings indicate that surface-based microstructures are necessarily not a correlation for corresponding estimates with leaf PM adsorption.

Seedlings of Pterocarpus indicus were grown in both well-watered and drought stress conditions in phytotron. Seedlings grown under well-watered and drought stress conditions were exposed to either combined or without ozone of 200 ppb for one month. First, the physiological responses to elevated ozone levels indicated a decreased biomass. The seedlings grown in arid soil and exposed to ozone showed less biomass than those grown in arid soil but not exposed to ozone. Moreover, all the seedlings except the well-watered and unexposed ones showed a significantly lower photosynthetic rate (PN) over time. However, with the accumulation of ozone injuries, the antioxidant enzyme activities increased overall. In the study results, when exposed to ozone, the well-watered seedlings exhibited more antioxidative enzyme activity than did the seedlings grown in arid soil. Generally, P. indicus in arid soil suffered less damage from elevated ozone than did the well-watered plants.

The present study was conducted to examine the response of Pterocarpus indicus to elevated ozone by comparing the effects between well-watered and soil drought treatments. The ozone concentration was 200 ppb and the exposure was conducted for a month with well-watered and soil drought treatments in chamber environmental conditions. Elevated ozone-induced visible injuries to P. indicus varied among the well-watered environmental conditions, with the appearance of light green chlorosis in the SWO seedlings over time. However, in the SDO seedlings, no difference was visible between drought and drought with ozone treatment. Shriveled leaves were evident because of the water deficiency. Moreover, elevated ozone induced leaf stomata injury and a harsh abaxial surface, whereas drought stress induced less injured stomata because of stomata closing. In addition, the palisade tissues exhibited smaller chloroplasts, damaged thylakoid, increased plastoglobuli, decreased starch grain and thinner cell walls on the upper leaf surface. Thus, the SDO seedlings were less influenced by elevated ozone stress than SWO seedlings due to the reduced ozone absorption which caused by stomata closing to prevent water loss.

In recent decades, airborne allergens for allergic respiratory diseases have been found to increase significantly by a process of converting coniferous forests into broad-leaved forests in Korea. This study was conducted to evaluate factors, including airborne pollen counts, micromorphology, and flowering phenology, that can affect oak pollen-related allergic symptoms. The catkin of Mongolian oak (Quercus mongolica Fisch. ex Ledeb.) showed the most rapidly blooming catkin on Julian day 104 in flower development. Among six species, the last flowering was observed on Julian day 119 in Korean oak (Quercus dentata Thunb.). The pollen dispersal was persisted for about 32 days from Julian day 104 to Julian day 136. Airborne pollen was observed about 2 weeks after flowering phase H, the senescence phase. Pollen size varied by species, with the largest from Q. mongolica (polar axis length, PL = 31.72 &micro, m, equatorial axis length, EL = 39.05 &micro, m) and the smallest from Jolcham oak (Quercus serrata Murray) (PL = 26.47 &micro, m, EL = 32.32 &micro, m). Regarding pollen wall structure, endexine of Q. dentata was coarsely laminated or fragmented. The endexine thicknesses of Sawtooth oak (Quercus acutissima Carruth.) and Q. serrata were thick and stable, whereas Galcham oak (Quercus aliena Blume), Q. mongolica, and Oriental cork oak (Quercus variabilis Blume) had thinner endexines. The area occupied by pollenkitt of Q. variabilis was significantly larger than that of Q. acutissima. Importantly, Q. variabilis had a distinctly thick 17 kDa protein band, a presumed major allergen. Oak species differ in pollen protein composition, and thus there is a possibility that the allergenic activity of pollen proteins vary depending on oak species. This study highlights the fact that native oak species in Korea differ in flowering pattern of male flowers, pollen morphology, and pollen chemical constituents. These discrepancies in flowering and pollen properties imply variable allergic responses to oak pollen from different species.

Global warming and ozone (O3) pose serious threats to crop yield and ecosystem health. Although neither of these factors will act individually in reality, most studies have focused on the responses of plants to air pollution or climate change. Interactive effects of these remain poorly studied. Therefore, this study was conducted to assess the effects of optimal (22/20 &deg, C day/night) and elevated temperature (27/25 &deg, C) and/or ambient (10 &plusmn, 10 nL L&minus, 1) and elevated O3 concentrations (100 &plusmn, 1) on the growth, physiology, and reactive oxygen species (ROS) accumulation of leaf mustard (Brassica juncea L.). The aim was to examine whether elevated temperature increase the O3 damage due to increasing stomatal conductance, and thus, O3 flux into the leaf. Significant reductions in photosynthetic rates occurred under O (elevated O3 with optimal temperatures) and OT (elevated O3 and temperature) conditions compared to C (controls). Stomatal conductance was significantly higher under T than in the C at 7 DAE. Under OT conditions, O3 flux significantly increased compared to that in O conditions at 7 days after exposure (DAE). Significant reductions in total fresh and dry weight were observed under OT conditions compared to those under O. Furthermore, significant reductions in levels of carotenoids and ascorbic acid were observed under OT conditions compared to O. Lipid peroxidation and accumulation of ROS such as hydroxyl radical, hydrogen peroxide, and superoxide radical were higher under O and OT conditions than in C conditions at 7 and 14 DAE. As a result of O3 stress, the results of the present study indicated that the plant injury index significantly increased under OT compared to O conditions. This result suggested that elevated temperature (+5 &deg, C) may enhance O3 damage to B. juncea by increasing stomatal conductance and O3 flux into leaves.

Carbon sequestration in agroforestry systems plays an important role for climate change regulation. Policy makers make use of growth models for carbon estimations of the large scale projects in designing regulation. This study revealed the aboveground carbon sequestration potentials and established allometric growth models of four species in agroforestry. Based on the results, the aboveground carbon storages of Morinda tinctoria Roxb., Terminalia oliveri Brandis., Rhus paniculata Wall. and Emblica officinalis Gaertn. were 6.88, 6.59, 4.34 and 3.53 kg C tree−1, respectively. In comparison between two types of agroforestry, a mixture of M. tinctoria and E. officinalis had a higher carbon sequestration potential (1331 kg C ha−1) than a mixture of R. paniculata and T. oliveri (1151.40 kg C ha−1). A hyperbolic growth model and a basic quadratic model were the best-fit models for R. paniculata and E. officinalis, respectively, while a basic logarithmic model was the best fit for both M. tinctoria and T. oliveri. This study highlighted that both Akaike Information Criterion, Furnival index and coefficient of determination should be taken into consideration for model selection, as opposed to only considering the coefficient of determination. The study also pointed out that a mixture of M. tinctoria and T. oliveri should be considered as a tentative model for agroforestry plantations to enhance the carbon storage in semi-arid area in the future.

Plants can undergo external fluctuations in the natural light and dark cycle. The photosynthetic apparatus needs to operate in an appropriate manner to fluctuating environmental factors, especially in light. Yellow-poplar seedlings were exposed to nighttime artificial high-pressure sodium (HPS) lighting to evaluate night light-adaptation strategies for photosynthetic apparatus fitness relative to pigment contents, photosystem II photochemistry, photosynthetic parameters, histochemical analysis of reactive oxygen species, and plant biomass. As a result, seedlings exhibited dynamic changes including the enhancement of accessory pigments, the reduction of photosystem II photochemistry, increased stomatal limitation, downregulation of photosynthesis, and the decreased aboveground and belowground biomass under artificial night lighting. Histochemical analysis with 3,3′-diaminobenzidine (DAB) and nitroblue tetrazolium (NBT) staining indicates the accumulation of in situ superoxide radicals (O2−) and hydrogen peroxide (H2O2) in leaves exposed to the lowest level of artificial night lighting compared to control. Moreover, these leaves exposed to artificial night lighting had a lower nighttime respiration rate. These results indicated that HPS lighting during the night may act as a major factor as repressors of the fitness of photosynthesis and growth patterns, via a modification of the photosynthetic light harvesting apparatus.

An understanding of how species diversity, structural pattern, and species distribution vary across different environmental regions is crucially important for tropical ecology. In this study, we explored how these ecological parameters vary across various rainfall regions in the tropics with annual rainfall levels ranging from 843 to 2035 mm. Diversity, similarity, structure, and forest classification, and their correspondence with rainfall regions were tested. We found that species diversity, site class, and structural complexity increased with rainfall, with differences of 1000 mm having significant effects on diversity. The structure and heterogeneity of forests were higher in the high rainfall regions than the low rainfall regions. The forest structure was significantly correlated with rainfall, and the structure differed substantially where annual rainfall differed among sites by approximately 200 or 400 mm. Forests could be classified into two types according to whether they had high annual rainfall (1411–2035 mm) or low annual rainfall (843–1029 mm). In addition, the dominance of species changed noticeably from high- to low-rainfall regions, with Tectona hamiltoniana and Terminalia oliveri only being abundant in the low rainfall region. Species diversity and richness were significantly correlated with rainfall and average temperature. These findings will provide invaluable information for forest management and ecological phytogeography.

Global warming is a well-known natural phenomenon that needs to be controlled for environmental conservation. Based on the ecological interrelationship between forest and climate, the concept of our review was formulated with the aim of providing current information about deforestation and its effects on climate change, the impacts of climate change on forests and the role of forests in climate change. Based on recent research findings, the annual rate of deforestation is 0.14% per year with 2.3 million square kilometers lost between 2000 and 2012. The net carbon emission from deforestation and forest degradation, which can cause climate change, was high and it has not changed significantly over the last two decades. On the other hand, temperature, drought, precipitation and fire can affect forest health (especially for young trees). But if we define these factors in detail, solar radiation alone may not affect tree growth, although together with temperature it can affect growth. Moreover, the frequency o...

This study was intended to find out the benefits of forests, especially for non-wood forest products (NWFPs), to forest-dependent local people and the relation to their socio-economic status. Sampling (169 respondents) was chosen to be an equal distribution of household's economic status. The survey was conducted face to face with structural interviews using both open-and closed-ended questions. The results showed that bamboo and bamboo shoot were considered as the most collected NWFPs in the Bago Yoma region. The average consumptions of NWFPs were 302.50 ± 90.12 viss to 501.27 ± 120.65 viss. Furthermore, the research revealed that the collection of NWFPs showed negative correlation with income availability and livestock possession. The study aims to help provide the necessary information for sustainable forest management.

Nowadays, the intensive management and huge pressure from the human population has become a great challenge for efficient forest management. The main focuses of this study are to investigate (1) the current socio-economic status of a forest-dependent community and (2) the social contribution of two environmental conservation efforts – remnant natural forest conservation and plantation establishment – in a comparative way. The structural interview method was used for the survey, and questionnaires were set out as both closed- and open-ended questions. The respondents were stratified as poor, medium and better off, and the sample shape was defined as a triangle. The results showed that restoration by means of remnant forest conservation gave much more tangible and intangible benefits than plantations. The mean value of fuelwood availability from natural forests was significantly higher than that of the plantation forests, whereas most of the local people depended on both types of forests for their supplies....

Home garden is a traditional agroforestry system, which is an ecologically and socio-economically sustainable land use system in West Java, Indonesia. It plays a fundamental role in providing subsistence food and income to local people through a multi-strata structure. Despite the importance of the home garden, which is strongly linked with quality of living, there is still a lack of quantitative data and information. Therefore, we quantified the economic and ecological characteristics of home gardens in the present study to evaluate their diverse roles. In addition, general strategies that are applicable to home gardens in West Java were developed for sustainable management. The results of this study indicated that: (1) large landholding size showed a significantly higher Net Present Value (NPV) than small landholding size when the home gardens were dominated by fruit tree species, (2) species richness, species diversity, and carbon stock did not differ significantly among the different types and sizes of home gardens in West Java, and (3) multi-layered and diverse species composition is considerable for sustainable management of home gardens in terms of income generation and against urbanization and commercialization in West Java, Indonesia. Further studies should be considered for developing a standardized and generalized model that is able to evaluate and quantify the various ecosystem values that are generally acceptable and applicable in rural areas.

Although urban trees are proposed as comparatively economical and eco-efficient biofilters for treating atmospheric particulate matter (PM) by the temporary capture and retention of PM particles, the PM removal effect and its main mechanism still remain largely uncertain. Thus, an understanding of the removal efficiencies of individual leaves that adsorb and retain airborne PM, particularly in the sustainable planning of multifunctional green infrastructure, should be preceded by an assessment of the leaf microstructures of widespread species in urban forests. We determined the differences between trees in regard to their ability to adsorb PM based on the unique leaf microstructures and leaf area index (LAI) reflecting their overall ability by upscaling from leaf scale to canopy scale. The micro-morphological characteristics of adaxial and abaxial leaf surfaces directly affected the PM trapping efficiency. Specifically, leaf surfaces with grooves and trichomes showed a higher ability to retain PM as compared to leaves without epidermal hairs or with dynamic water repellency. Zelkova serrata (Thunb.) Makino was found to have significantly higher benefits with regard to adsorbing and retaining PM compared to other species. Evergreen needle-leaved species could be a more sustainable manner to retain PM in winter and spring. The interspecies variability of the PM adsorption efficiency was upscaled from leaf scale to canopy scale based on the LAI, showing that tree species with higher canopy density were more effective in removing PM. In conclusion, if urban trees are used as a means to improve air quality in limited open spaces for urban greening programs, it is important to predominantly select a tree species that can maximize the ability to capture PM by having higher canopy density and leaf grooves or trichomes.

This experiment was conducted to investigate the effect of interaction between water and light on growth and cell structure in Ulmus pumila L. One-year-old seedlings grown in a greenhouse at the University of Seoul were used in this study. Ulmus pumila seedlings were subjected to three light treatments, full sunlight (HI), 30% of full sunlight (MI), 10% of full sunlight (LI) and under well watered (WW) and water stressed (WS) conditions. Following reduction of irradiance, thinner leaf thickness could be examined by light microscopy. In HI leaf thickness increased due to larger palisade and spongy parenchyma cells. This study suggests that leaf tissue morphological characteristics was affected by light but not water conditions.

Understanding the patterns of land-cover change for biodiversity and ecology system function has been important in landscape ecology. The objective of this study was to analyze land-cover change in the Ain Snoussi area of northern Tunisia. Landsat MSS/4 and SPOT HRV/3 images were used for the analysis. To classify land-cover type into forest and non-forest area, pixel-based classification and maximum likelihood algorithm were applied to two imageries using supervised classification algorithm. After classification of images, each changed area was calculated. Thereby, analysis of distance roads and topographic factors such as elevation, slope, aspect, and Topographic Wetness Index (TWI) were performed. The results showed that the area changed into non-forest was slightly larger than that into forest. Moreover, most of the changed areas, approximately half of the total changed area, were distributed near the roads. In addition, the change from forest to non-forest area tends to have a negative and positive r...

The objective of this study was to collect basic data for medicinal ingredients such as ginsenosides (Re and Rb1) contents grown in forests in Korea. To achieve this purpose, 10 forest stands have been selected in various mountain areas. Agricultural cultivated ginseng was used to compare with ginsenosides of forest ginseng. Rb 1 and Re contents of forest ginseng grown in 10 forests were higher than agricultural cultivated ginseng. Regionally, Rb1, and Re contents of the Panax ginseng grown in Jeongsun, Sangju and Namyangju were generally higher than those of 10 other forests in Korea

Four‐year‐old seedlings of Pinus densiflora were inoculated with a suspension of B. xylophilus, or B. mucronatus adjusted to 3,000 nematodes per 50 μL sterilized distilled water in a greenhouse on July 21, 2008 to evaluate initial symptom development and the changes of gas exchange rate. B. xylophilus and B. mucronatus were distinguished by four restriction enzymes except Rsa I, and the result of ITS‐RFLP of B. xylophilus used in this experiment was completely matched to that of pine wood nematode reported previously. Needle dehydration and subsequent yellowing were observed in all seedlings inoculated with B. xylophilus isolate while the appearance of the seedlings was normal in all seedlings inoculated with B. mucronatus and control. Needle dehydration was observed in most seedlings inoculated with B. xylophilus between 2 and 3 weeks after inoculation. In seedlings inoculated with B. xylophilus, continuous decrease in photosynthetic rate was observed after 6 days of inoculation. Photosynthetic rate decr...

This paper presents a corporate volunteer‐based strategy for initiating and sustaining forest restoration efforts in Mt. Makiling, Philippines that evolved within the last decade. The strategy, dubbed “conservation relay”, is a process where various private sectors carry out and support restoration efforts in sequential time periods, attending an area from its degraded status to a condition favoring natural restoration processes. From 1993 to 2006, about 830 individuals belonging to 14 companies/groups contributed to the rehabilitation of 31.5 hectares of degraded forest areas in Mt. Makiling. Recent research on the impacts of these efforts in one of the sites showed substantial improvement in vegetation cover, species composition, microclimate, and soil conditions that now favor natural regeneration processes

Changes in the resistance of stomatal transpiration following abscisic acid (ABA) treatment were investigated in four species of broad‐leaved trees that underwent artificial shade treatment. In all four species, Betula platyphylla, Betula schmidtii, Zelkova serrata and Acer mono, the light environment exerted a significant influence on the differences of stomatal transpiration and its changes. The time series changes among the four tree species showed varied tendencies according to the type of treatment and level. In the case of Acer mono, Betula platyphylla and Betula schmidtii, transpiration resistance increased following ABA solution treatment at a low concentration of 0.02 mmol. In addition, the differences were increased according to artificial shade treatment levels and with the passage of time. In the case of Zelkova serrata following ABA treatment at a concentration of 0.05 mmol, seedlings which were developed in a high shade treatment with a back‐light rate of 6% showed a high transpiration resis...

Natural regeneration is an essential component of forest dynamics and the recovery of ecosystem functions. Therefore, understanding regeneration status, and how abiotic and biotic factors affect it, is important for ecological studies. This study discovered different regeneration statuses of tropical forests in response to differences in rainfall in Myanmar, and the environmental and overstory factors that had the most influence on understory regeneration. Study sites were set up in regions with 625 to 2035 mm of annual rainfall, and ecological characteristics were measured. According to the results, natural regeneration increased with rainfall, showing a good regeneration status at all sites. Forests within a range of 1411–2035 mm of annual rainfall had a significantly higher density and species diversity at specific natural regeneration stages than those with 625–1029 mm. Not only abiotic but also overstory structure affected the natural regeneration of forests. However, not all factors influenced natural regeneration status. Overstory size distribution parameters did not show a significant influence on natural regeneration. Average annual rainfall (abiotic), as well as ecosystem complexity, density, species richness, and diversity (overstory), were found to be the most influential factors for the density and diversity of natural regeneration. The results of this study will support silviculture and the management of tropical forests.

Growth and photosynthetic responses of dwarf apple saplings (Malus domestica Borkh. cv. Fuji) acclimated to 3 years of exposure to contrasting atmospheric CO2 concentrations (360 and 650 µmol mol–1) in combination with current ambient or elevated (ambient +5°C) temperature patterns were determined. Four 1-year-old apple saplings grafted onto M.9 rootstocks were each enclosed in late fall 1997 in a controlled environment unit in nutrient-optimal soil. Soil moisture regimes were automatically controlled by drip irrigation scheduled at 50 kPa of soil moisture tension. For the elevated CO2 concentration alone, overall tree growth was suppressed. However, tree growth was slightly enhanced when warmer temperatures were combined with the elevated CO2 concentration. Neither temperature nor CO2 concentration affected leaf chlorophyll content and stomatal density. The elevated CO2 concentration decreased mean leaf area, but increased starch accumulation, thus resulting in a higher specific dry mass of leaves. An elevated temperature reduced starch accumulation. Light-saturated rates of leaf photosynthesis were suppressed due to the elevated CO2 concentration, but this effect was removed or enhanced with warmer temperatures. The elevated CO2 concentration increased the optimum temperature for photosynthesis by ca. 4°C, while the warmer temperature did not. The results of this study suggested that the long-term adaptation of apple saplings to growth at an elevated CO2 concentration may be associated with a potential for increased growth and productivity, if a doubling of the CO2 concentration also leads to elevated temperatures.