• Journal of Ecology and Environment
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• v.34 no.3
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• pp.295-305
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• 2011

Many studies have suggested the positive effects of grazing by large herbivorous mammals on seed dispersal, but little is known about how herbivores could affect the fate of ingested seeds. This study examined the effects of seed ingestion by sika deer (Cervus nippon) on seed fate in a temperate grassland established in an urban park long resided by high densities of sika deer. I compared species composition and seasonal traits of seed abundance and maturity in the grassland community with those in deer fecal pellets. In total, 27 herbaceous species were observed, including the predominant Zoysia japonica. Seed phenology and production differed among the three dominant species (Z. japonica, Digitaria violascens, and Hydrocotyle maritima). Pellets contained at least 26 species of herbaceous seeds, and their abundance differed among species. Of the 26 species, 15 were observed in the vegetation at the study site. The peak of seed abundance in pellets for the dominant species appeared 1 month after the peak of inflorescence production (but most of the inflorescences were immature and susceptible to digestion) and consequently corresponded to the peak of mature inflorescence. Because sika deer are likely to ingest seeds at any maturity stage in the grassland and immature seeds are less hardened, ingested immature seeds can suffer great losses. The results suggested that the survival of germable seeds with great losses of immature seeds may be a factor determining which plant species can be successfully dispersed by herbivores.

• Journal of Ecology and Environment
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• v.32 no.3
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• pp.137-143
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• 2009

Pre-dispersal seed predation by a granivorous bird, the masked grosbeak (Eophona personata, Fringillidae), was investigated in two bird-dispersed trees, Celtis sinensis and Aphananthe aspera (Ulmaceae). The objectives of this study were to 1) measure direct damage of predation by grosbeaks on plant crops, 2) reveal the temporal pattern of predation within each tree species and its causal factors, and 3) test whether foraging grosbeaks hinder foraging of frugivorous birds, thereby indirectly impacting the reproduction of both tree species. A substantial amount of fruit and seed crop was consumed by grosbeaks (24.3% in Celtis; 55.5% in Aphananthe), and only 17.7% (Celtis) and 16.7% (Aphananthe) were removed by frugivorous birds. At the study site, the grosbeak population size fluctuated greatly during the fruiting seasons of both plant species. As for Celtis, predated seed density also fluctuated temporally, and the local population size of grosbeaks was responsible for predated seed density. In Aphananthe, predation was not fully explained by grosbeak populations or plant phenology, but its peak coincided with that of grosbeak population. These results suggest that predispersal seed predation by granivorous birds can have large negative impacts on the bird-dispersed plants. Changes in local population size of granivorous birds can influence predatation and can affect reproductive success of the bird-dispersed plants available to the birds.

• Journal of Environmental Science International
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• v.22 no.12
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• pp.1633-1641
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• 2013

The objective of this study was to analyze correlation between phenological characteristics of Salix spp. and meteorological factors in the Upo wetlands. Phenology of Salix subfragilis Andersson and Salix chaenomeloides Kimura was monitored from 2007 to 2012. Meteorological variables were monitored by Korea Meteorological Administration (Hap-chon). Average date of flowering, fruiting, seed dispersion was 86, 113, 136 days for S. subfragilis and 112, 140, 164 days for S. chaenomeloides as Julian days. Flowering of S. subfragilis and S. chaenomeloides were correlated with daily mean air temp. in March (r=-0.92, r=-0.85, p<0.05). Fruiting of S. subfragilis was correlated with total precipitation between Jan and March of previous year (r=-0.90, p<0.01), however, the fruiting of S. chaenomeloides was highly correlated with max. temp. in Jan of previous year (r=0.99, p<0.01). Seed dispersion of both species is correlated with min. temp. in Feb. Phenology monitoring will contribute to understanding Salix spp. response against climate change.

• Journal of Marine Bioscience and Biotechnology
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• v.11 no.2
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• pp.62-70
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• 2019

We investigated the variation of morphological features, density, biomass and characteristics of reproductive shoot on Zostera marina. This species was monthly monitored and collected during a year in Tongyeong (from January 2016 to December 2016). Morphological features, biomass and density showed significantly seasonal variation (p<0.001). Dimensions of Z. marina were highest in spring and early summer but lowest in winter. Biomass and leaf density of Z. marina showed highest value in May (4,700.5 g w·wt m^-2) and June (858.0 leaves m^-2) respectively and lowest value in November (515.9 g w·wt m^-2 and 312.0 leaves m^-2). Reproductive shoot was monitored from April (13℃) to June (21℃) and grew up to ca. 200 cm. Spathe length, spadix weight, numbers and weight of fruit showed significantly different on monthly. None mature flowers were monitored in April but matured flowers, fruits were founded in May and seed releasing were occurred in June.

• Journal of Forest and Environmental Science
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• v.28 no.1
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• pp.1-7
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• 2012

Tropical forests whether fragmented or undisturbed or be they equatorial or deciduous, remain the storehouse of biodiversity for hundreds of thousands of plant and animal species. This unique characteristic continues to attract a wide range of scientists and international organizations to study and attempt to understand tropical forest ecosystems. Gene flow is mediated by pollen, seed and seedling dispersal, and factors affecting this gene flow include phenology, spatial distribution, population structures, seed predation, sexual and mating systems as well as physical and biological barriers to gene flow. Two methods are used in measuring gene flow: direct method that relies on the actual observation of seed and pollen dispersal, whereas indirect methods involve the use of genetic markers such as allozymes and DNA techniques. Political strife, extreme natural and artificial disasters, the lack of a comprehensive forestry research vision, coupled with difficult socio-economic conditions in Africa have made the environment quite difficult for sustained research activities on the part of those undertaking or wishing to undertake such studies. Gene flow studies in this region are few and far between. This review elaborates on the mechanisms of gene flow mediation in Sub-Saharan Africa.

• Korean Journal of Agricultural and Forest Meteorology
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• v.20 no.2
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• pp.159-165
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• 2018

The seed yield of summer plants is affected by climate change due to high temperature. High temperature during the reproductive growth period decrease pod, seed weight in soybean. This study was conducted at National Institute of Crop Science (NICS) during the growing season. The objective of this study was to determine the effect of high temperature on growth and seed yield responses of soybean varieties using a temperature gradient chamber (TGC). In 2017, the Daewonkong (DWK), Pungsannamulkong (PSNK), and Deapungkong (DPK) were grown in three TGCs. Four temperature treatments, Ta (near ambient temperature), Ta+1 (ambient temperature+$1^{\circ}C$), $Ta+2^{\circ}C$ (ambient temperature+$2^{\circ}C$), $Ta+3^{\circ}C$ (ambient temperature+$3^{\circ}C$), $Ta+4^{\circ}C$ (ambient temperature+$4^{\circ}C$), were established by dividing the rows along which the temperature gradient was created. In all three cultivars, beginning bloom (R1) delayed at elevated temperature in $Ta+4^{\circ}C$. In addition, the days to beginning of seed fill and maturity were longer under higher temperature. The numbers of pod, 100 seed weight, and seed yield increased at elevated temperature in DWK. In contrast, seed yield components of PSNK and DPK were reduced in $Ta+4^{\circ}C$. The results suggest that 100 seed weight and seed size of soybean was low by increased temperature in $Ta+4^{\circ}C$ of PSNK and DPK.

• Journal of Forest and Environmental Science
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• v.25 no.1
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• pp.1-24
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• 2009

Teak (Tectona grandis) is one of the most valuable timber yielding species in the world, with predominant distribution in tropical or sub-tropical countries. However, natural teak available only in few countries like India, Myanmar, Laos People's Democratic Republic and Thailand. Teak grows well in deep, well-drained alluvial soils, fairly moist, warm, tropical climate with pH ranges from 6.5-7.5. Teak is cultivated in many Asian, African and South American countries for timber production. The global teak plantations are estimated to be three million hectare with major share in India (44%) followed by Indonesia (33%). India is considered as richest genetic resources of teak with large areas of natural teak bearing forests (8.9 million ha), plantations (1.5 million ha), clonal seed orchards (1000 ha) and seed production areas (5000 ha). The studies on diversity of teak populations showed that teak is an out crossing species with major portion of diversity present within the populations. The productivity and quality of teak timber varies depending upon the site and environmental conditions. Teak wood is moderately heavy, strong and tough,straight grained, coarse textured and ring porous with specific gravity varies from 0.55 to 0.70. The sapwood is white to pale yellow in colour and clearly demarcated while heartwood is dark brown or dark golden yellow in colour. Teak is one of the most durable timbers in the world, practically, impervious to fungus and white ant attack and resistant to decay. Teak wood is used in ship and boat constructions, furnitures and aesthetic needs. Genetic improvement programmes have been undertaken in countries like Thailand, India, Malaysia and Indonesia. The programme includes provenance identification and testing, plus tree selection and clonal multiplication, establishment of seed orchards and controlled hybridization. Several aspects like phenology, reproductive biology, fruit characteristics, silvicultural practices for cultivation, pest and diseases problems, production of improved planting stock, harvesting and marketing, wood properties and future tree improvement strategy to enhance productivity have been discussed in this paper.

• Korean Journal of Ecology and Environment
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• v.46 no.3
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• pp.380-387
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• 2013

The objective of this study is to investigate the effect of elevated $CO_2$ and temperature on the phenology and reproductive ecological characteristics of Bupleurum latissimum. We measured characteristics of 4-year-old B. latissimum grown under control (ambient $CO_2$+ambient temperature, 340~370 ppm) and treatment (elevated $CO_2$+elevated temperature, 690~770 ppm) conditions in a glass house. The period of flowering, fruit appearance and fruit maturing was earlier by 4, 1, 2 days, respectively, under elevated $CO_2$ and temperature. The comparative weight of a single ripe fruit, all ripe fruits and total ripe and unripe fruits was higher per control than treated plants. However the other characteristics, such as no. of peduncle, matured fruits, total fruits per plant and fruit setting rate per plant of B. latissimum were not significantly affected by elevated $CO_2$ and temperature. The germination rate of B. latissimum was higher in control than in treatment plants. These results showed that the phenology of B. latissimuin might be well suited to an earlier growing season, and the response of reproductive characteristics of B. latissimuin is negatively influenced by global warming.

• Korean Journal of Agricultural and Forest Meteorology
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• v.14 no.4
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• pp.229-235
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• 2012

This study was conducted to investigate the climatic factors affecting bud phenology of Pinus densiflora provenances. Data were collected from Jungseon, Chungju and Jeju plantations which were parts of the 11 provenance trials established by Korea Forest Research Institute in 1996. The 36 provenances were included in this trial ($33^{\circ}30^{\prime}{\sim}38^{\circ}08^{\prime}$ in latitude and $126^{\circ}30^{\prime}{\sim}129^{\circ}20^{\prime}$ in longitude). The bud swelling date and bud burst date of the provenances were investigated from March to May in 2004 in two-day interval. The four geographic factors and fifteen climatic factors of the test sites and provenances were considered in this study. Canonical correlation analysis was conducted to examine the major factors affecting the bud phenology. Our results suggested that the major factors affecting the timing of bud swelling and burst are the differences in latitude, longitude, extremely low temperature (during December-February), extremely high temperature (during November-February) and annual mean growing days between test plantation and provenance. The provenances with lower winter temperature than that of plantation showed the faster bud swelling and bud burst. Based on these results, the implication on the seed transfer of P. densiflora was discussed.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.64 no.4
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• pp.395-405
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• 2019

A recent assessment by the Intergovernmental Panel on Climate Change projected that the global average surface temperature will increase by a value 1.5℃ from 2030 to 2052. In this study, we used a temperature gradient chamber that mimicked field conditions to evaluate the effect of increased air temperature on phenology, yield components, protein content, and oil content, to assess soybean growth. In 2017 and 2018, 'Deawonkong', 'Pungsannamulkong', and 'Deapungkong' cultivars were grown in three temperature gradient chambers. Four temperature treatment groups were established by dividing the rows along temperature regimes: ambient temperature + 1℃ (aT+1), ambient temperature + 2℃ (aT+2), ambient temperature + 3℃ (aT+3), ambient temperature + 4℃ (aT+4). Year, cultivar, and temperature treatments significantly affected yield components and seed yield. In 2017, the flowering stage of 'Deawon' and 'Pungsannamul' cultivars in the aT+4 group was delayed compared to the flowering stage of those in the aT+1 group. In 2018, the flowering stage of 'Deawon' and 'Pungsannamul' was delayed at all temperature gradients, owing to high temperature stress, whereas 'Deapung' was regularly flowering in 2017 and 2018. The duration of the grain filling period was six days shorter in 2018 than in 2017 because of high temperature stress. The total number of pods per ㎡ for 'Deawon' and 'Pungsannamul' was 48.8 and 41.5% lower in 2018 than in 2017, respectively, whereas 'Deapung' increased by 6.3%. The 100-seed weight of 'Deawon' and 'Deapung' was 29.2 and 32.1% lower, respectively. However, 'Pungsannamul' decreased by 14.7%. The protein and oil content was lower during the grain filling period in 2018 than in the same period in 2017 because of high temperature stress. In contrast, the oil content in 'Deapung' was higher in 2018 than in 2017. Our results showed that increased temperature during the grain filling period was significantly and negatively correlated with pod number, 100-seed weight, protein content, and oil content.