• Title/Summary/Keyword: perennials

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Characterizing soils and the enduring nature of land uses around the Lake Chamo Basin in South-West Ethiopia

  • Zebire, Degife Asefa;Ayele, Tuma;Ayana, Mekonen
    • Journal of Ecology and Environment
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    • v.43 no.2
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    • pp.129-160
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    • 2019
  • Background: Characterizing and describing soils and land use and make a suggestion for sustainable utilization of land resources in the Ethiopian Rift valley flat plain areas of Lake Chamo Sub-Basin (CSB) are essential. Objectives: To (1) characterize soils of experimental area according to World Reference Base Legend and assess the nature and extent of salinity problems; (2) characterize land use systems and their role in soil properties; and (3) identify best land use practices used for both environmental management and improve agricultural productivity. Methods: Twelve randomly collected soil samples were prepared from the above land uses into 120 composites and analyzed. Results: Organic carbon (OC) and total nitrogen (TN) were varied along different land uses and depleted from the surface soils. The soil units include Chernozems (41.67%), Kastanozems (25%), Solonchaks (16.67%), and Cambisols (16.67%). The identified land uses are annual crops (AA), perennial crops (PA), and natural forest (NF). Generally, organic carbon, total nitrogen, percentage base saturation (PBS), exchangeable (potassium, calcium, and magnesium), available phosphorus (P2O5), manganese, copper, and iron contents were decreased in cultivated soils. Soil salinity problem was observed in annuals. Annuals have less nutrient content compared to perennials in irrigated agriculture while it is greater in annuals under rainfed. Clay, total nitrogen, available phosphorus, and available potassium (K2O) contents were correlated positively and highly significantly with organic carbon and electrical conductivity. Conclusion: Management practices that improve soil quality should be integrated with leguminous crops when the land is used for annual crops production.

Ecological Characteristics of Village Groves in Bijeon-dong, Pyeongtaek City, Gyeonggi-do Province, Korea (경기도 평택시 비전동 마을숲의 생태적 특성)

  • Ahn, Young-Hee;Park, Eun-Jin;Choe, Chang-Yong
    • Journal of Environmental Science International
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    • v.18 no.5
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    • pp.527-538
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    • 2009
  • A village grove is the one fostered and protected for a district's traditional life near the vicinity of a ruderal village. This research is done to grasp potential natural vegetation, to use a basis data needed for its management and preservation as well as restoration project by examining the vegetation and flora targeting a village grove of the southern district of Gyeonggi-do which has been seriously damaged subsequent to a rapidly progressing city development. According to the survey, there appeared an outgrowth flora of Pteridophyta consisting of 69 families, 136 genera, 20 varieties, 3 forms, 170 species-totalling to 193 taxa. Urbanization index was revealed to 4.55% and naturalization rate 6.74%. In life-cycle pattern, perennials were found to show the highest distribution rate; in infiltration-multiplication strategies, human wave tactics type was found to be the highest 51%, consisting of 98 species, and naturalization rate also was revealed to be 6.74%. The vegetation unit was divided into a total of 11 patterns, such as a community of Pinus densiflora community, Pinus densiflora-Pinus rigida community, Pinus densiflora-Castanea crenata community, Pinus rigida community, Pinus rigida-Castanea crenata community, Pinus rigida-Quercus acutissima community, Castanea crenata community, Castanea crenata-Quercus acutissima community, Quercus acutissima community, Quercus acutissima-Robinia pseudo-acacia community and Robinia pseudo-acacia community. Quercus acutissima community is of a community type dominated by Quercus acutissima, in place of Pinus densiflora community selected by natural succession.

Changes in Plant Species on a Grass Roof over Time (초지지붕에서의 시간경과에 따른 식생변화)

  • Lee, Young-Moo
    • Journal of the Korean Institute of Landscape Architecture
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    • v.34 no.6 s.119
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    • pp.39-53
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    • 2007
  • Unlike conventional roof landscaping, where various kinds of plants and structures are employed, a grass roof is a roof on which herbaceous plants are grown in planting medium and which is not accessed or maintained, mainly because it doesn't have sufficient load capacity to support a regular roof garden. They are mostly built on existing roofs, whether flat slab or gabled. Planting on roofs has numerous advantages, such as creating a biotope, purifying urban air, adding moisture to the atmosphere, storing rain water, preventing flash floods, reducing energy use for heating and air conditioning, enhancing the urban landscape and providing relaxation to the city dwellers, not to mention the alleviation of global warming by absorbing $CO_2$. In addition to the general merits of roof planting, the grass roof has its own unique qualities. Only herbaceous species are planted on the roof, resulting in light weight which allows roofs of existing buildings to be planted without structural reinforcement. The species chosen are mostly short, tough perennials that don't need to be maintained. These conditions provide an ideal situation where massive planting can be done in urban areas where roofs are often the only and definitely the largest space available to be planted. If roofs are planted on a massive scale they can play a significant role in alleviating global warming, heat island effects and energy shortages. Despite the advantages of grass roofs, there are some problems. The most significant problem is the invasion of neighboring plants. They may be brought in with the planting medium, by birds or by wind. These plants have little aesthetic value comparing to the chosen species and are usually taller. Eventually they dominate and prevail over the original species. The intended planting design disappears and the roof comes to look wild. Since the primary value of a grass roof is ecological, a change in attitude towards what constitutes beauty on the roofscape is necessary. Instead of keeping the roof neat through constant maintenance, people must learn that the wild grass with bird's nests on their roof is more beautiful as it is.

Ecological Studies of Plants for Control of Environmental Pollution, III -The Studies on the Content and Contamination of Heavy Metals and Vegetation of Roadside- (환경오염 방지를 위한 식물의 생태학적 연구(III) -도로변 식생과 중금속 함량 및 오염에 관한 연구)

  • 차종환
    • Journal of Plant Biology
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    • v.17 no.4
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    • pp.158-162
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    • 1974
  • Some ecological attributes of perennial plants and Pb contamination were analyzed for study plots near an entrance of Nevade Test Site at Mercury Valley, Nye County, Nevada. The surface of the desert pavement soil was composed of stones (1 to 4cm diameter). The underside of each stone was coated with coarse and fine sand (about 90%). The profiles of soil were constituted with the A-horizon and C-horizon only. The soil pH at the plots ranges from 7.6 to 8.5, C/N was 13 and cation exchange capacity showed 15me/100g. Nine species and 42 number of individuals were found in all plots. Franseria dumosa and Larrea divaricata were dominant species. The discrete clumps of vegetation were consisted of 9 species of common perennials and these were covered about 25% on desert pavement, on the other words, bare area without vegetation was about 75%. The size and spacing of the plants was irregular. Community coefficient as comparison between shrub species in these study area and those in near the low elevation desert indicated a low degree of similarity. Density, cover and productivity in the study plots as compared with those in the nearest study areas in Mercury Valley showed a higher value. The soils in the studied area involved high heavy metal contents in the plant tissue was higher than those of its soil. The leavds of Lycium andersonii tended to accumulate more Zn and Mo than those of the other species. Larrea divaricata leaves accumulated very high leaves of Fe and Ephedra nevadensis were generally high in Mn. Lead contamination was apparent in foliage of desert vegetation collected alongside the roadway, reflecting the variation in traffic volume. Lead contents greater than fifteen-fold of normal (low traffic) were found in plant foliage alongside the heavily traveled roadway. Lead content of old foliage by the heavily traveled roadway was as much as 129 ppm but that of new foliage 17 ppm only.

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Molecular phylogenetic relationship of the family Colchicaceae (Liliales)

  • Thi, Nguyen Pham Anh;Kim, Jung-Sung;Kim, Joo-Hwan
    • Proceedings of the Plant Resources Society of Korea Conference
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    • 2012.05a
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    • pp.19-19
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    • 2012
  • The Colchicaceae comprising 250 species and 15-19 genera of rhizomatous or cormous perennials, the moderate sized family in Liliales, distributes widely through the temperate and tropical areas of Africa, Asia and North America. The division of two subfamilies in Colchicaceae is still unclear because of different results in previous studies. Moreover, sister taxa of this family has not been determined. In genus level, it was uncertain that whether expand circumscription of three genera of Colchicum, Gloriosa, and Wurmbea which are include Androcymbium, Littonia and Onixotis, respectively, is reasonable or not. In this study, three coding genes of atpB, matK and rbcL were analyzed to reconstruct phylogenetic relationship of Colchicaceae and both of maximum parsimony (MP) and Bayesian analysis were conducted. Among three genes, matK region was most variable and provided more parsimony-informative sites, whereas the atpB and rbcL regions were similar in the variation and number of informative characters. Monophyly of Colchicaceae was strongly supported and it was divided into two subfamilies (Wurmbeoideae and Uvulariodeae). Uvularia-Disporum clade, comprises the subfamily Uvularioideae, is a sister of the rest Colchicaceae and subsequently differentiated Burchardia was a sister within subfamily Wurmbeoideae. Burchadia was used to be supposed to be a sister of the family in the previous studies. It was clear the monophyly and phylogenetic relationship among six tribes sensu Vinnersten and Manning (2007) within the family. In addition, the expanded circumscription of three genera was also strongly supported; Colchicum-Androcymbium (BP99), Wurmbea-Onixotis (BP100), and Littonia-Gloriosa (BP100). Here, we propose a re-circumscription among taxa of Colchicaceae.

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Allozyme Diversity in Korean Populations of Calystegia soldanella and C. japonica (Convolvulaceae): Implications for Conservation

  • Chung, Myong Gi
    • Journal of Plant Biology
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    • v.38 no.2
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    • pp.173-180
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    • 1995
  • We investigated levels and distribution of genetic variation in Korean populations of Calystegia soldanella and C. japonica, clonally reproducing herbaceous perennials. Calystegia soldanella is one ofecologically important beach plants growing only on sand and beach dunes in Europe, East Asia, the Pacific Islands, and the west coast of North America. In contrast, C. japonica usually grows on small mounds of paddy fields, roadsides, and waste places with patchy distribution. Starch gel electrophoresis was conducted on leaves collected from 13 populations of C. soldanella and eight populations of C. japonica. The levels of genetic variation of the two species are very comparable; means of expected heterozygosity (Hep) were 0.100 and 0.099 for C. soldanella and C. japonica, respectively. These values were also very similar to those for species with similar life-history and ecological traits. However, the proportion of total genetic diversity partitioned among populations (GST) of C. soldanella (0.146) was considerably lower than that of C. japonica (0.383). In addition, means of Nei's genetic identity (Ⅰ) for C. soldanella and C. japonica were 0.985 and 0.900, respectively, which supports a restricted gene flow resulting from obligate clonal reproduction of C. japonica. Significant differences in allele frequency were detected among populations at eight and nine of nine polymorphic loci for C. soldanella and C. japonica (P<0.01), respecitvely. Considering the ecological importance of C. soldanella, the isolated beach populations coupled with present destruction of natural habitats of the species may result in erosion of genetic diversity in the near future. In this respect, conservation efforts should be focused on those populations that currently maintain the most genetic diversity such as those populations in the eastern and southeastern Korean Peninsula and Hamduck Beach, Cheju Island.

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The Relationship between the Soil Seed Bank and Above-ground Vegetation in a Sandy Floodplain, South Korea

  • Cho, Hyung-Jin;Jin, Seung-Nam;Lee, Hyohyemi;Marrs, Rob H.;Cho, Kang-Hyun
    • Ecology and Resilient Infrastructure
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    • v.5 no.3
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    • pp.145-155
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    • 2018
  • In a monsoonal climate, the soil seed bank can play an important role in plant regeneration after the severe annual floods that disturb above-ground vegetation within the riparian zone. To investigate the relationship between the soil seed bank and vegetation, we measured the species composition of the soil seed bank and the extant above-ground vegetation in six major plant communities (Artemisia selengensis, Miscanthus sacchariflorus, Persicaria nodosa, Phalaris arundinacea, Phragmites japonica, and Rorippa palustris) in the Cheongmicheon Stream, Korea. A total of 21 species germinated from the floodplain soil seed banks. The most diverse seed bank (21 species) was found in the A. selengensis community, wheres the lowest number of species was found in the R. palustris community (2 species). Most soil seed banks were composed of annuals (90%), exceptions being Rumex crispus and Artemisia princeps, which are perennial ruderals. The similarity of species composition between the soil seed bank and above-ground vegetation was low with Sorensen's similarity indices averaging 29% (range 12 - 42%). Crucially, existing dominant perennials of the extant vegetation including A. selengensis, M. sacchariflorus, P. japonica and P. arundinacea were absent from the soil seed bank. In conclusion, the soil seed banks of the floodplains of the Cheongmicheon Stream were mainly composed of viable seeds of ruderal plants, which could germinate rapidly after severe flood disturbance. The soil seed bank may, therefore, be useful for the restoration of the early succession stages of riparian vegetation after flood disturbances.

Weeds Identified in the Buryingplaces of the Kyungpook Probince (경북지방(慶北地方)의 묘지(墓地)에 분포(分布)하는 잡초종(雜草種))

  • Kim, K.U.;Shin, D.H.;Kwon, S.T.;Park, S.J.;Lee, S.J.
    • Korean Journal of Weed Science
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    • v.13 no.2
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    • pp.164-172
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    • 1993
  • About 196 weed species composed of 31 annuals, 38 biennials and 127 perennials belonging to 53 families were identified from 90 buryingplaces in Kyungpook province on June and September, 1992. Compositae was the most widely occuring family covering 34 species, followed by 27 species in graminae, 17 species in leguminosae, and 10 species in rosaceae, 8 species in liliaceae ranunculaceae, 7 species in caryophyllaceae cruciferae, 6 species in labiate polygonaceae, 4 species in crassulaceae cyperaceae, and the rest 41 families having 1 to 3 species. The dominant weed species occured in the buryingplaces based on importance value and frequency were Imperata cylindrica, Artemisia princeps, Viola mandchrica, Erigeron annuus, Erigron canadensis, Rubus parvifolius and Prunella vulgaris.

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A Survey of Weeds Occurrence on Paddy Fields in Gyeongbuk Province in Korea (경북지역 논 잡초 발생분포 조사)

  • Kim, Sang Kuk;Kim, Hak Yoon
    • Weed & Turfgrass Science
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    • v.3 no.1
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    • pp.6-12
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    • 2014
  • The survey of weed occurrence was conducted to identify problem weed species in the paddy field. The 320 sites of the 13 regions in Gyeongbuk Province were investigated from June to July, 2013. In the whole region, 51 weed species were identified including 34 annuals and 17 perennials. The highest importance value of annual weed and perennial was dominant 88.4 and 48.7%, in Gumi region, respectively. The most dominant weed species in paddy fields of Gyeongbuk Province were Monochoria vaginalis var. plantaginea (10.80%), followed by Lemna paucicostata (10.74%), Bidens tripartite (8.77%), Echinochloa oryzoides (7.17%), and Scirpus juncoides (6.20%). The similarity of paddy weeds in 13 regions observed through TWINSPAN analysis was distinguished by Ludwigia prostrata, Scirpus juncoides, Lindernia dubia, Polygonum aviculare, and Alopecurus aequalis var. amurensis. The weed species, Ludwigia prostrata, was divided into the four regions, Gyeongju, Gumi(direct seeding cultivation), Youngcheon and Euiseong and ten regions, Gumi, Bonghwa, Sanju, Goryung, Youngdeog, Pohang, Sanju, Andong, Yecheon, and Cheongdo.

The Variation in the Species Composition of the Soil Seed Bank in the Natural Flood Plain Vegetation along the Urban Reach of Han River, South Korea

  • Lee, Hyo-Hye-Mi;Marrs, Rob H.;Lee, Eun-Ju
    • Korean Journal of Ecology and Environment
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    • v.44 no.1
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    • pp.42-57
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    • 2011
  • We described the above-ground plant species composition and measured a range of soil physico-chemical properties and the composition and size of the soil seed bank in the remnant natural vegetations on the flood plains of the Han River within Seoul, South Korea. We used analysis of variance and multivariate analyses to analyse the data and S${\o}$rensen's similarity index to compare the composition of the vegetation and seed banks. The soils were circum-neutral and composed of mainly sand and silt fractions with a very limited clay component; a gradient based on sand/clay proportions was identified. The soil seed banks varied markedly between- and within-sites and had much greater species diversity than the above-ground vegetation. Two of the major dominants in the vegetation (Miscanthus saccariflorus and Phragmites australis) were found at very low densities in the seed bank. The site differences appeared to be correlated with the sand-clay gradient, suggesting that the soil properties differentially affected seed inputs into the soil, or that the processes than controlled sediment deposition during floods was also important in differentially affecting seed deposition. Lastly, there was relatively little similarity between the vegetation, dominated mainly by perennials, and the seed bank which contained a relatively large proportion of annuals and biennials. This result suggests that after disturbance caused by flooding there is the potential for many other species to colonize. This may impinge on the regeneration potential of the sites and cause concern for the future conservation of these important remnants of natural vegetation.