Forest Decline Under Progress in the Urban Forest of Seoul, Central Korea

Vegetation in the urban area showed not only a difference in species composition but also lower diversity compared with that of the natural area. Successional trend was normal in natural area, but that in urban areas showed a retrogressive pattern. Korean mountain ash (Sorbus alnifolia (Siebold & Zucc.) K.Koch), a shade intolerant species, dominated such a retrogressive succession. The vegetation decline is due to changes of mesoclimate and soil properties that imbalanced distribution of green space induced as the result of urbanization. In recent years, new environmental stress due to climate change is imposed additively to this forest decline. Drought is the very environmental stress. Drought-induced plant damage started from withering of leaves of plants introduced for landscaping in the urban area. Over time, branches died and death of the whole plant body followed. In particular, damage of Korean mountain ash, the product of retrogressive succession, was remarkable. As retrogressive succession has already progressed much, thus such phenomenon could be recognized as crisis of urban forest

Generation and analysis of large-scale expressed sequence tags (ESTs) from a full-length enriched cDNA library of porcine backfat tissue

BACKGROUND: Genome research in farm animals will expand our basic knowledge of the genetic control of complex traits, and the results will be applied in the livestock industry to improve meat quality and productivity, as well as to reduce the incidence of disease. A combination of quantitative trait locus mapping and microarray analysis is a useful approach to reduce the overall effort needed to identify genes associated with quantitative traits of interest. RESULTS: We constructed a full-length enriched cDNA library from porcine backfat tissue. The estimated average size of the cDNA inserts was 1.7 kb, and the cDNA fullness ratio was 70%. In total, we deposited 16,110 high-quality sequences in the dbEST division of GenBank (accession numbers: DT319652-DT335761). For all the expressed sequence tags (ESTs), approximately 10.9 Mb of porcine sequence were generated with an average length of 674 bp per EST (range: 200–952 bp). Clustering and assembly of these ESTs resulted in a total of 5,008 unique sequences with 1,776 contigs (35.46%) and 3,232 singleton (65.54%) ESTs. From a total of 5,008 unique sequences, 3,154 (62.98%) were similar to other sequences, and 1,854 (37.02%) were identified as having no hit or low identity (<95%) and 60% coverage in The Institute for Genomic Research (TIGR) gene index of Sus scrofa. Gene ontology (GO) annotation of unique sequences showed that approximately 31.7, 32.3, and 30.8% were assigned molecular function, biological process, and cellular component GO terms, respectively. A total of 1,854 putative novel transcripts resulted after comparison and filtering with the TIGR SsGI; these included a large percentage of singletons (80.64%) and a small proportion of contigs (13.36%). CONCLUSION: The sequence data generated in this study will provide valuable information for studying expression profiles using EST-based microarrays and assist in the condensation of current pig TCs into clusters representing longer stretches of cDNA sequences. The isolation of genes expressed in backfat tissue is the first step toward a better understanding of backfat tissue on a genomic basis

Urban effluent discharge into rivers; a forensic chemistry approach to evaluate the environmental deterioration

Development of urban area provides deterioration of natural resources in the environment. Aliphatic hydrocarbons are among important chemical that show spatial changes. Fifteen surface sediment samples were collected using Ekman dredger to monitor the features of aliphatic hydrocarbons in tributaries of Likas River on December 2011. Samples were extracted using Soxhlet, followed 2 steps column chromatography then injected into GC-MS for instrumental analysis. The results show that northern tributary remained natural with odd carbon number dominance. The study has found fresh petroleum input into Inanam River where more urban development and transportation activities are existed by presence of major hydrocarbons such as C18 and C20. The values of Carbon Preferences Index indicated that natural hydrocarbons entry from land is decreasing towards estuaries where marine input increases. Construction, transportations and urban activities around southern tributary of Inanam River have deteriorated drastically the quality of the environment. The study concluded that aquatic environments such as river are susceptive to anthropogenicactivities. This research can scientifically monitor new residential developments environmental effects happening at the northern part of Darau River in the study area. The current approach may be employed to observe the rehabilitation programs in the environment

Expression analysis and functional characterization of the monosaccharide transporters, OsTMTs, involving vacuolar sugar transport in rice (Oryza sativa)

In Arabidopsis, the compartmentation of sugars into vacuoles is known to be facilitated by sugar transporters. However, vacuolar sugar transporters have not been studied in detail in other plant species. To characterize the rice (Oryza sativa) tonoplast monosaccharide transporters, OsTMT1 and OsTMT2, we analysed their subcellular localization using green fluorescent protein (GFP) and expression patterns using reverse-transcription polymerase chain reaction (RT-PCR), performed histochemical beta-glucuronidase (GUS) assay and in situ hybridization analysis, and assessed sugar transport ability using isolated vacuoles. Expression of OsTMT-GFP fusion protein in rice and Arabidopsis revealed that the OsTMTs localize at the tonoplast. Analyses of OsTMT promoter-GUS transgenic rice indicated that OsTMT1 and OsTMT2 are highly expressed in bundle sheath cells, and in vascular parenchyma and companion cells in leaves, respectively. Both genes were found to be preferentially expressed in the vascular tissues of roots, the palea/lemma of spikelets, and in the main vascular tissues and nucellar projections on the dorsal side of the seed coats. Glucose uptake studies using vacuoles isolated from transgenic mutant Arabidopsis (tmt1-2-3) expressing OsTMT1 demonstrated that OsTMTs are capable of transporting glucose into vacuoles. Based on expression analysis and functional characterization, our present findings suggest that the OsTMTs play a role in vacuolar glucose storage in rice

Distribution, Effect, and Control of Exotic Plants in Republic of Korea

This study was carried out to clarify the spatial distribution of exotic plants at national, regional, and local levels, as well as their ecological impacts, and to prepare a strategy to reduce the impacts in Republic of Korea. This study was attempted at the national, regional, and local levels throughout Republic of Korea. Compositae occupied the highest percentage among invading exotic plants in Republic of Korea. A review of the biological attributes of exotic plants based on the dormancy form, longevity, disseminule form, growth form, and radicoid form showed that therophytes, annual plants, plants that disperse seeds by gravity (D4), erect form (E), and nonclonal growth form (R5) occupied the highest proportion. At the national level, the spatial distribution of exotic plants tended to depend on topographic conditions such as elevation and slope degree, and to increase around urbanized areas, agricultural fields, and coastal areas. The habitat types that exotic plants established were similar in their native habitat and in Korea, where they invaded. They preferred disturbed land such as roadsides, bare ground, agricultural fields, and so on. The spatial distribution of vegetation types dominated by exotic plants was restricted in the lowland. The proportion of the exotic/native plants tended to proportionate reversely to the vegetation type richness (the number of vegetation types); that is, the ecological diversity. The proportion of the exotic plants was higher in artificial plantations, vegetation due to disturbance, and vegetation established on lower slopes compared with upper slopes. Even at the local level, the exotic plants appeared abundantly in the introduced vegetation, while they were rare in the native ones. In the vegetation infected by exotic species, not only the species composition changed significantly, but the species diversity also decreased. Restorative treatment by introducing mantle vegetation around the hiking trail inhibited the establishment of exotic plants. Further, the restoration practice recovered the similarity of the species composition compared to the reference vegetation and increased the species diversity

Spatial Distribution of Vegetation on Stream Bars and the Riparian Zone Reflects Successional Pattern Due to Fluid Dynamics of River

The river is a dynamic space where erosion, transportation, and sedimentation are constantly occurring due to running water. This study aims to reveal the change in geomorphology caused by the flow characteristics of water in rivers and the response of vegetation to that. This study was carried out by clarifying the spatially appearing successional trends in the vegetation established in the stream bars and the riparian zones, which are located on different topographic conditions based on the vegetation profile, ordination result, and species diversity. The spatial distribution of vegetation on the stream bars tended to appear in the order of annual plant-, perennial plant-, and tree-dominated stands from the upstream toward a downstream direction (a gravel bar and a sand bar in a mountain gravel-bed river and an estuary, respectively) or the reversed one (a sand bar in a lowland river). The spatial distribution of vegetation on the riparian zones tended to appear in the order of annual plant-, perennial plant-, and tree-dominated stands from the waterfront toward the bank direction. Changes in species composition also differed depending on the spatial location, showing a similar trend to the spatial distribution of vegetation. Species diversity became higher in proportion to the longevity of the dominant species of each vegetation type. In conclusion, the longitudinal distribution pattern of vegetation on the stream bars resembles the lateral distribution of riparian vegetation, and the successional trends follow the spatial distribution pattern. These results suggest that the dynamics of bed loading, an allogenic process, may be an important determinant of the spatial distribution and succession of plant communities in dynamic riverine environments

Phenological Changes of Mongolian Oak Depending on the Micro-Climate Changes Due to Urbanization

Urbanization and the resulting increase in development areas and populations cause micro-climate changes such as the urban heat island (UHI) effect. This micro-climate change can affect vegetation phenology. It can advance leaf unfolding and flowering and delay the timing of fallen leaves. This study was carried out to clarify the impact of urbanization on the leaf unfolding of Mongolian oak. The survey sites for this study were established in the urban center (Mts. Nam, Mido, and Umyeon in Seoul), suburbs (Mts. Cheonggye and Buram in Seoul), a rural area (Gwangneung, Mt. Sori in Gyeonggi-do), and a natural area (Mt. Jeombong in Gangwon-do). Green-up dates derived from the analyses of digital camera images and MODIS satellite images were the earliest in the urban center and delayed through the suburbs and rural area to the natural area. The difference in the observed green-up date compared to the expected one, which was determined by regarding the Mt. Jeombong site located in the natural area as the reference site, was the biggest in the urban center and decreased through the suburbs and rural area to the natural area. Green-up dates in the rural area, suburbs, and urban center were earlier by 11.0, 14.5, and 16.3 days than the expected ones. If these results are transformed into the air temperature based on previous research results, it could be deduced that the air temperature in the urban center, suburbs, and rural area rose by 3.8 to 4.6 °C, 3.3 to 4.1 °C, and 2.5 to 3.1 °C, respectively. Green-up dates derived based on the accumulated growing degree days (AGDD) showed the same trend as those derived from the image interpretation. Green-up dates derived from the change in sap flow as a physiological response of the plant showed a difference within one day from the green-up dates derived from digital camera and MODIS satellite image analyses. The change trajectory of the curvature K value derived from the sap flow also showed a very similar trend to that of the curvature K value derived from the vegetation phenology. From these results, we confirm the availability of AGDD and sap flow as tools predicting changes in ecosystems due to climate change including phenology. Meanwhile, the green-up dates in survey sites were advanced in proportion to the land use intensity of each survey site. Green-up dates derived based on AGDD were also negatively correlated with the land use intensity of the survey site. This result implies that differences in green-up dates among the survey sites and between the expected and observed green-up dates in the urban center, suburbs, and rural area were due to the increased temperature due to land use in the survey sites. Based on these results, we propose conservation and restoration of nature as measures to reduce the impact of climate change

Assessment of the Carbon Budget of Local Governments in South Korea

This study was carried out to assess the carbon budget of local governments in South Korea. The carbon budget was obtained from the difference between net ecosystem productivity (NEP) that the natural ecosystem displays, and carbon dioxide emissions calculated from energy consumption in each local government. NEP was obtained from the difference between net primary productivity, measured by an allometric method, and soil respiration, measured with EGM-4 in natural forests and artificial plantations. Heterotrophic respiration was adjusted to 55% level of the total soil respiration based on existing research results. A field survey to obtain information for components of the carbon cycle was conducted in Cheongju (central Korea) and Yeosu (southern Korea). Pinus densiflora, Quercus acutissima, and Quercus mongolica (central Korea) and P. densiflora and Q. acutissima (southern Korea) forests were selected as the natural forests. Pinus rigida and Larix kaempferi (central Korea) and P. rigida (southern Korea) plantations were selected as the artificial plantations. Vegetation types were classified by analyzing LandSat images by applying a GIS program. CO2 emissions were the highest in Pohang, Gwangyang, and Yeosu, where the iron and the petrochemical industrial complexes are located. CO2 emissions per unit area were the highest in Seoul, followed by Pohang and Gwangyang. CO2 absorption was the highest in the Gangwon province, where the forest area ratio to the total area is the highest, and the lowest in the metropolitan areas such as Seoul, Incheon, Daegu, Daejeon, and Gwangju. The number of local governments in which the amount of absorption is more than the emission amount was highest in Gangwon-do, where 10 local governments showed a negative carbon budget. Eight, seven, five, five, three, and three local governments in Gyeongsangbuk-do, Jeollanam-do, Gyeongsangnam-do, Jeollabuk-do, Gyeonggi-do, and Chungcheongbuk-do, respectively, showed a negative carbon budget where the amount of carbon absorption was greater than the emission amount. The carbon budget showed a very close correlation with carbon emission, and the carbon emission showed a significant correlation with population size. Moreover, the amount of carbon absorption showed a negative correlation with population size, population density, and non-forest area, and a positive correlation with the total area of the forest, coniferous forest area, and broad-leaved forest area. Considering the reality that carbon emissions exceed their absorption, measures to secure absorption sources should be considered as important as measures to reduce carbon emissions to achieve carbon neutrality in the future. As a measure to secure absorption sources, it is proposed to improve the quality of existing absorption sources, secure new absorption sources such as riparian forests, and efficiently arrange absorption sources

Assessment of the Carbon Budget of Local Governments in South Korea

This study was carried out to assess the carbon budget of local governments in South Korea. The carbon budget was obtained from the difference between net ecosystem productivity (NEP) that the natural ecosystem displays, and carbon dioxide emissions calculated from energy consumption in each local government. NEP was obtained from the difference between net primary productivity, measured by an allometric method, and soil respiration, measured with EGM-4 in natural forests and artificial plantations. Heterotrophic respiration was adjusted to 55% level of the total soil respiration based on existing research results. A field survey to obtain information for components of the carbon cycle was conducted in Cheongju (central Korea) and Yeosu (southern Korea). Pinus densiflora, Quercus acutissima, and Quercus mongolica (central Korea) and P. densiflora and Q. acutissima (southern Korea) forests were selected as the natural forests. Pinus rigida and Larix kaempferi (central Korea) and P. rigida (southern Korea) plantations were selected as the artificial plantations. Vegetation types were classified by analyzing LandSat images by applying a GIS program. CO2 emissions were the highest in Pohang, Gwangyang, and Yeosu, where the iron and the petrochemical industrial complexes are located. CO2 emissions per unit area were the highest in Seoul, followed by Pohang and Gwangyang. CO2 absorption was the highest in the Gangwon province, where the forest area ratio to the total area is the highest, and the lowest in the metropolitan areas such as Seoul, Incheon, Daegu, Daejeon, and Gwangju. The number of local governments in which the amount of absorption is more than the emission amount was highest in Gangwon-do, where 10 local governments showed a negative carbon budget. Eight, seven, five, five, three, and three local governments in Gyeongsangbuk-do, Jeollanam-do, Gyeongsangnam-do, Jeollabuk-do, Gyeonggi-do, and Chungcheongbuk-do, respectively, showed a negative carbon budget where the amount of carbon absorption was greater than the emission amount. The carbon budget showed a very close correlation with carbon emission, and the carbon emission showed a significant correlation with population size. Moreover, the amount of carbon absorption showed a negative correlation with population size, population density, and non-forest area, and a positive correlation with the total area of the forest, coniferous forest area, and broad-leaved forest area. Considering the reality that carbon emissions exceed their absorption, measures to secure absorption sources should be considered as important as measures to reduce carbon emissions to achieve carbon neutrality in the future. As a measure to secure absorption sources, it is proposed to improve the quality of existing absorption sources, secure new absorption sources such as riparian forests, and efficiently arrange absorption sources