• Title/Summary/Keyword: Vegetation Density

Search Result 418, Processing Time 0.023 seconds

Prosopis juliflora invasion and environmental factors on density of soil seed bank in Afar Region, Northeast Ethiopia

  • Shiferaw, Wakshum;Bekele, Tamrat;Demissew, Sebsebe;Aynekulu, Ermias
    • Journal of Ecology and Environment
    • /
    • v.43 no.4
    • /
    • pp.400-420
    • /
    • 2019
  • The aims of the study were to analyze (1) the effects of Prosopis juliflora (Prosopis) on the spatial distribution and soil seed banks (SSB) diversity and density, (2) the effects of environmental factors on SSB diversity and density (number of seeds in the soil per unit area), and (3) the effects of animal fecal droppings on SSB diversity, density, and dispersal. Aboveground vegetation data were collected from different Prosopis-infested habitats from quadrats (20 × 20 m) in Prosopis thickets, Prosopis + native species stand, non-invaded woodlands, and open grazing lands. In each Prosopis-infested habitats, soil samples were collected from the litter layer and three successive soil layer, i.e., 0-3 cm, 3-6 cm, and 6-9 cm. Seeds from soil samples and animal fecal matter were separated in the green house using the seedling emergence technique. Invasion of Prosopis had significant effects on the soil seed bank diversity. Results revealed that the mean value of the Shannon diversity of non-invaded woodlands was being higher by 19.2%, 18.5%, and 11.0% than Prosopis thickets; Prosopis + native species stand and open grazing lands, respectively. The seed diversity and richness, recovered from 6-9-cm-deep layer were the highest. On the other hand, the density of Prosopis seeds was the highest in the litter layer. About 156 of seeds/kg (92.9%) of seeds were germinated from cattle fecal matter. However, in a small proportion of seedlings, 12 of seeds/kg (7.1%) were germinated from shot fecal matter. Thus, as the seeds in the soil were low in the study areas, in situ and ex situ conservation of original plants and reseeding of persistent grass species such as Cynodon dactylon, Cenchrus ciliaris, Chrysopogon plumulosus, and Brachiaria ramosa are recommended.

Analysis of Forest Vegetation in Chungcheongnam-do Provincial Park of Korea (충청남도 도립공원 산림 식생 분석)

  • Kim, Hyoun-Sook;Park, Gwan-Soo;Lee, Sang-Myong;Lee, Joongku;Kim, Junghyun
    • Korean Journal of Environment and Ecology
    • /
    • v.32 no.5
    • /
    • pp.513-531
    • /
    • 2018
  • This study compared forest vegetation in Chungcheongnam-do Provincial Park (Deogsan, Chilgabsan, and Daedunsan) from 2006 to 2016. The results of the analysis on the vegetation of the research sites by the phytosociological method showed that the Deogsan Provincial Park had Quercus mongolica community, Pinus densiflora community, Q. variabilis community, and Zelkova serrata community. Chilgabsan Provincial Park had Q. variabilis community, Q. mongolica community, P. densiflora community, and Carpinus laxiflora community. Daedunsan Provincial Park had Q. mongolica community, Q. variabilis community, Q. serrata community, C. tschonoskii community, C. laxiflora community, P. densiflora community, and Q. acutissima community. The importance value in each Provincial Parks was analyzed as follows. The importance value of Q. mongolica(72.35) was the highest in Deogsan Provincial Park, and followed by P. densiflora(70.25), Q. variabilis(53.11), Styrax japonicus(11.44), Prunus sargentii(11.17), and Fraxinus rhynchophylla(10.41). Q. variabilis(73.34) was the highest in Chilgabsan Provincial Park and followed by, P. densiflora(58.71), Q. mongolica(57.02), C. laxiflora(18.84), Q. serrata(13.48), and Prunus sargentii(13.31). The importance value of Q. mongolica(57.03) was the highest in Daedunsan Provincial Park and followed by Q. variabilis(31.98), Q. serrata(31.53), P. densiflora(16.80), C. tschonoskii(16.50), C. laxiflora(16.07), S. obassia(15.76), and Acer pseudosieboldianum(10.09). The results of DBH analysis of the major species having the high importance value showed the normal density distirbution of Q. mongolica, and Q. variabilis in Deogsan Provincial Park, so the dominance status of these species is likely to continue. Q. variabilis, Q. mongolica, and P. densiflora in Chilgabsan Provincial Park showed the normal density distribution showed the density of normal distribution, so the dominance status of these species is likely to continue. However, the dominance status of C. laxiflora, and Q. serrata is likely to be expanded in the future due to the high density of young individuals. Q. mongolica, and Q. variabilis in Daedunsan Provincial Park showed the density of reverse J-shaped curve, so the dominance status of these species is likely to continue, and C. tschonoskii, and P. densiflora had a formality distribution, suggesting continuous domination of these species over the other species for the time being. Additionally the dominance status of C. laxiflora, and Q. serrata is considered to be expanded in the future due to the high density level of young individuals.

Vegetation Structure, Regeneration Niche, and Dynamics of the Saplings in Abies koreana Forest of the Mt. Chiri (지리산(智異山) 구상나무임분(林分)의 식생구조(植生構造)와 치수(稚樹) 발생(發生) 및 생육(生育) 동태(動態))

  • Chung, Jae Min;Lee, Soo Won;Lee, Kang Young
    • Journal of Korean Society of Forest Science
    • /
    • v.85 no.1
    • /
    • pp.34-43
    • /
    • 1996
  • We investigated the vegetation structure, and effects of canopy degree(gap or purlieu to 25%, 50%, 75%, over 75%) of the overstory on seedling regeneration and survivorship, and sapling density, growth and growth type of Abies koreana in subalpine of Mt. Chiri. The stem density in Abies koreana stand was higher in middle story than upper story, individual trees in upper story occupied larger area and were more apart, resulted in uniform distribution. The regeneration and survivorship of seedlings and saplings were best in 25% of crown closure, in order of 50%, gap, but lowest in over 75% of crown closure. The annual growth rate and recent 5 years growth rate of saplings were highest in gap or purlieu and getting lower toward gradually higher coverage of overstory. And 10- to 20-Year-old saplings were mainly regenerated in stands with lower density(I or II), but most of 20 to 30 years old saplings were growing in stands with higher density (III or IV). The number of "A" type saplings grown normally in gap or purlieu was gradually decreased in stand with higher density but the number of "D" or "E" types of which growth was supressed or prohibited by the high density was abruptly increased. Saplings normally growing in the gap and purlieu showed the panicle type, but those grown under dense crown were greatly suppressed and showed the umbellate type.

  • PDF

Ecological Studies on Korean White Pine Forest (I) - On the Undergrowth Vegetation - (잣나무 식재림(植栽林)의 생태학적(生態學的) 연구(硏究) (I) - 하층식생(下層植生)에 대하여 -)

  • Chon, Sang Keun;Chong, Hyon Pae
    • Journal of Korean Society of Forest Science
    • /
    • v.12 no.1
    • /
    • pp.13-21
    • /
    • 1971
  • As one part of the ecological studies of Korean white pine plantation, a synecological survey was made on the undergrowth vegetation of Korean white pine plantations of different age class i.e., 5, 15, 25, 35, and 40 year age classes under which shrub and ground vegetation were distinctly different. And, the results are summarized as follows. 1. In shrub, the important species is Corylus heterophylla var. japonica and the dominant species in each age-class stand are as follows; 5 year-class ; Quercus mongolica, Lespedeza Maximowiczi. 15 year-class ; Corylus heterophylla var. japonica, Lespedeza Maximowiczi. 25 year-class ; Corylus heterophylla var. japonica. 35 year-class ; Corylus heterophylla var. japonica, Maackia amurensis. 40 year-class ; Corylus heterophylla var. japonica. 2. The higher the age class of the plantation are, the lower the height and the density of the shrub become. 3. Dominant species of ground-vegetation under the shrub of each age-class are as follows; 5 year-class ; Arundinella hirta var. cilia, Miscanthus purpurascens. 15 year-class ; Arundinella hirta var. ciliata, Potentilla Freyniana. 25 year-class ; Physematium manchuriense, Viola xanthopetala, Rubus craegifolius. 35 year-class ; Viola xanthopetala, Rubus crataegifolius. 45 year-class ; Viola xanthopetala, Rubus crataegifolius. 4. The standing crops of ground vegetation under the shrub were decreased with increasing age-class, which also caused the decreasing height and density and changing floristic composition of the shrub. 5. The ratio of the standing crop of root to the standing crop of shoot was increased as the age class increased. 6. The floristic composition of ground vegetation has shown a change from heliophyte to sciophytes on the sere.

  • PDF

Impacts of Three-dimensional Land Cover on Urban Air Temperatures (도시기온에 작용하는 입체적 토지피복의 영향)

  • Jo, Hyun-Kil;Ahn, Tae-Won
    • Journal of the Korean Institute of Landscape Architecture
    • /
    • v.37 no.3
    • /
    • pp.54-60
    • /
    • 2009
  • The purpose of this study is to analyze the impacts of three-dimensional land cover on changing urban air temperatures and to explore some strategies of urban landscaping towards mitigation of heat build-up. This study located study spaces within a diameter of 300m around 24 Automatic Weather Stations(AWS) in Seoul, and collected data of diverse variables which could affect summer energy budgets and air temperatures. The study also selected reflecting study objectives 6 smaller-scale spaces with a diameter of 30m in Chuncheon, and measured summer air temperatures and three-dimensional land cover to compare their relationships with results from Seoul's AWS. Linear regression models derived from data of Seoul's AWS revealed that vegetation volume, greenspace area, building volume, building area, population density, and pavement area contributed to a statistically significant change in summer air temperatures. Of these variables, vegetation and building volume indicated the highest accountability for total variability of changes in the air temperatures. Multiple regression models derived from combinations of the significant variables also showed that both vegetation and building volume generated a model with the best fitness. Based on this multiple regression model, a 10% increase of vegetation volume decreased the air temperatures by approximately 0.14%, while a 10% increase of building volume raised them by 0.26%. Relationships between Chuncheon's summer air temperatures and land cover distribution for the smaller-scale spaces also disclosed that the air temperatures were negatively correlated to vegetation volume and greenspace area, while they were positively correlated to hardscape area. Similarly to the case of Seoul's AWS, the air temperatures for the smaller-scale spaces decreased by 0.32% ($0.08^{\circ}C$) as vegetation volume increased by 10%, based on the most appropriate linear model. Thus, urban landscaping for the reduction of summer air temperatures requires strategies to improve vegetation volume and simultaneously to decrease building volume. For Seoul's AWS, the impact of building volume on changing the air temperatures was about 2 times greater than that of vegetation volume. Wall and rooftop greening for shading and evapotranspiration is suggested to control atmospheric heating by three-dimensional building surfaces, enlarging vegetation volume through multilayered plantings on soil surfaces.

Riparian Vegetation Monitoring and Health Assessment by Pilot Opening of Nakdonggang River Estuary (낙동강하구 시범개방에 따른 수변식생 모니터링 및 건강성 평가)

  • Choi, Hyun-Gu;Kim, Hwa-Young;Lee, Jun-Yeol;Sohn, Byeong-Yong;Lee, Ji-Young
    • Korean Journal of Environment and Ecology
    • /
    • v.36 no.5
    • /
    • pp.445-459
    • /
    • 2022
  • In this study, we investigated current vegetation and assessed the health of vegetation through the KERVI (Korea Estuary Riparian Vegetation Index) to monitor vegetation changes near estuaries due to the opening of the Nakdong River estuary. As the first investigation of the long-term monitoring, six areas near the Nakdong River estuary were surveyed twice in July and October 2021, and vegetation monitoring and a survey of species composition and distribution density of aquatic, riparian, and land plants were carried out. The survey identified 262 taxa, 82 families, 192 genera, 196 species, 3 subspecies, 26 varieties, and 1 form of vascular plants in the surveyed area. The results of the vegetation health assessment through KREVI showed that sites 1 and 6 were rated "Very good" in both surveys, sites 2 and 4 were rated "Very good" in the first survey and then "Good"in the second survey, and site 3 and 5 were rated one grade higher in the second survey than the first survey. The assessment showed that the health grades of most species in the survey area were generally high. Most of the potential natural vegetation after the opening of estuary gates to create a brackish water area is expected to consist of reed (Phragmites communisTrin.) communities. The area of the willow (Salix koreensisAndersson) community adjacent to the water area may be somewhat narrower, but the community will be maintained. In the case of freshwater areas in inland areas with very low salinity, reeds (Phragmites communisTrin.) are expected to occupy most of them, and some communities such as amur silver-grass (Miscanthus sacchariflorusBenth.) and cattails (Typha orientalisC. Presl) are expected to be distributed. We suggest establishing measures such as estuary gate operation to create healthy brackish water regions through long-term monitoring.

Woody Plant Species Composition, Population Structure and Carbon Sequestration Potential of the A. senegal (L.) Willd Woodland Along a Distance Gradient in North-Western Tigray, Ethiopia

  • Birhane, Emiru;Gebreslassie, Hafte;Giday, Kidane;Teweldebirhan, Sarah;Hadgu, Kiros Meles
    • Journal of Forest and Environmental Science
    • /
    • v.36 no.2
    • /
    • pp.91-112
    • /
    • 2020
  • In Ethiopia, dry land vegetation including the fairly intact lowland and western escarpment woodlands occupy the largest vegetation resource of the country. These forests play a central role in environmental regulation and socio-economic assets, yet they received less scientific attention than the moist forests. This study evaluated the woody plant species composition, population structure and carbon sequestration potential of the A. senegal woodland across three distance gradients from the settlements. A total of 45 sample quadrants were laid along a systematically established nine parallel transect lines to collect vegetation and soil data across distance gradients from settlement. Mature tree dry biomass with DBH>2.5 cm was estimated using allometric equations. A total of 41 woody plant species that belong to 20 families were recorded and A. senegal was the dominant species with 56.4 IVI value. Woody plant species diversity, density and richness were significantly higher in the distant plots compared to the nearest plots to settlement (p<0.05). The cumulative DBH class distribution of all individuals had showed an interrupted inverted J-shape population pattern. There were 19 species without seedlings, 15 species without saplings and 14 species without both seedlings and saplings. A significant above ground carbon (5.3 to 12.7 ton ha-1), root carbon (1.6 to 3.6 ton ha-1), soil organic carbon (35.6 to 44.5 ton ha-1), total carbon stock (42.5 to 60.7 ton ha-1) and total carbon dioxide equivalent (157.7 to 222.8 ton ha-1) was observed consistently with an increasing of distance from settlement (p<0.05). Distance from settlement had significant and positive correlation with species diversity and carbon stock at 0.64⁎⁎ and 0.78⁎⁎. Disturbance intensity may directly influence the variation of species composition, richness and density along the A. senegal woodland. The sustainability of the A. senegal woodland needs urgent protection, conservation and restoration.

Effect of Split Nitrogen Application Times on Turf Vegetation of Creeping Bentgrass (질소 분시횟수가 Creeping Bentgrass 잔디초지의 식생에 미치는 영향)

  • Park, Sung-Jun;Cho, Nam-Ki;Kang, Young-Kil;Song, Chang-Khil;Cho, Young-Il
    • Journal of The Korean Society of Grassland and Forage Science
    • /
    • v.25 no.2
    • /
    • pp.119-124
    • /
    • 2005
  • This study was conducted from March 21 to July 8 in 2004 at JeJu Island to investigate the influences of split nitrogen application times on creeping bentgrass vegetation. Nitrogen rate was 20 kg/10a and it was applied from once to 5 times. The result obtained were summarized as follows; plant height was getting longer as nitrogen was split applied from once to 5 times. So it was longest at 5 times split nitrogen application, but it was no significance from 4 to 5 times. Root length, Minolta SPAD-502 chlorophyll meter reading value, leave and root weight n[e directly proportional plant height response. Degree of land cover Iud density of creeping bentgrass increased as nitrogen was split applied from once to 5 times. But degree of land cover md density of reed decreased. The number of reed species on decreased as nitrogen was split applied from once to 5 times. Then ranking of the dominant weeds were Portulaca oleracea Polygonum hydropiper and Stellaria media (at once split time nitrogen application), Portulaca oleracea, Polygonum hydropiper and Digitaria adscendens (at 2 split times nitrogen application), Digitaria adscendens and Portulaca oleracea Polygonum hydropiper, (at 3 split times nitrogen application), Portulaca oleracea, Poa annua and Polygonum hydropiper (at 4 md 5 split times nitrogen application). These results indicate that the optimum frequency of split N applications is four times for growth of creeping bentgrass in volcanic ash soils of Jeju island.

The Management Methods of Multi-Purpose Ecological Reservoir by System Thinking - Focused on Anteo Eco Park - (시스템 사고를 통한 다기능 생태저류지의 관리방안 - 광명 안터생태공원을 중심으로 -)

  • Lee, HyunJi;You, Soojin;Chon, Jinhyung
    • Journal of the Korean Society of Environmental Restoration Technology
    • /
    • v.18 no.2
    • /
    • pp.1-17
    • /
    • 2015
  • Ecological reservoir is a multifunctional space where provides the functions of retention, animal habitat and improvement of ecosystem health and landscape. The ecological reservoir of Anteo Eco Park located in Gwangmyeong-si has established to functions for water purification, maintenance of healthy aquatic ecosystem. Because the Anteo Eco Park is located in the site where nonpoint pollutant materials flow in, Anteo Eco Park has potential factors which aquatic ecosystem health deteriorates and damages the habitat of golden frog(Rana plancyi chosenica) which is restoration target species. Therefore, the purpose of this study is to suggest the plan to manage the variables which impede the right functions of aquatic ecosystem by understanding the causal loop diagram for the change of water quality environment and the interaction of predator-prey through system thinking. The results are as follows. First, the study showed that the individual number of golden frog which is an indicator species of Anteo Eco Park is threatened by snakeheaded fish, which is an upper predator. Therefore, balanced food chain should be hold to protect golden frog by capturing the snakeheaded fish which is individual number's density is high, and the monitoring management of the individual number for predator(snakeheaded fish)-prey(golden frog) should be performed. Second, the study represented that water pollution and carnification is caused by the sediment as the dead body of the large emergent vegetation in the winter cumulates as sediment. Ecological reservoir in Anteo Eco Park has been managed by eliminating the dead body of the large emergent vegetation, but the guideline for the proper density maintenance of vegetation community is additionally needed. Lastly, the study showed that aquatic ecosystem of Anteo Eco Park where is contaminated from the inflow of nonpoint pollutants affects the individual number's decline of golden frog and snakeheaded fish. Accordingly, the creation of a buffer area and a substitution wetland is needed in the periphery of the Anteo Eco Park to control the inflow of nonpoint pollutants including organic matters, nutrients and heavy metals. This study will be helpful that Anteo Eco Park improves the regional landscape and maintain healthy aquatic ecosystem space for the park visitors including local residents.

A Planting Plan of Buffer-Forest Belts on the Waste Landfill Sites -In the Case of the Boundary Area at the SUDOKWON Landfill Site- (폐기물매립지 완층수림대 식재계획 사례연구 -수도권매립지 경계지역을 대상으로-)

  • Cho, Ju-Hyoung;Choi, Mi-Jin
    • Journal of the Korean Society of Environmental Restoration Technology
    • /
    • v.5 no.5
    • /
    • pp.58-66
    • /
    • 2002
  • We present a planting plan of the buffer-forest belts created at the boundary area of the waste landfill site which is located in the coastal area of Kyubg-Gi province. In order to form a proper section of ground soil excavated from the sea and a forest which shows a distinction of the vegetation stratification, the planting plan with trees, sub-trees, shrubs, and seedlings (produced at a sprout cultivation place) is devised with an adjustment of planting density. 1. The preparation of mounding is required for planting at a waste landfill site. We first estimate an economical and efficient banking height together with the quantity of soil, and prepare a planting ground with excavated ground soil for the consideration of soil recycling. On the planting ground a banking with a height of 1.5-2m is produced by self-supported soil, playing a role in a salt blocking and an irritation layer of planting. Finally, an additional banking with a height of 2m is produced by qualified vegetation soil, forming a vegetation section with a total height of 6m. 2. Since the planning site is located in the border, the planting area is composed of two regions : one is an inclined face (slope 1 : 3) toward the inside of the landfill site and the other is an inclined face (slope 1 : 4) toward the inland. The buffer planting in the former (latter) region consists of wind break forest (mixed-landscape forest) within a width of less than 35m. 3. Based on the data obtained from the literatures and the investigation of local plants, we choose the 21 plant species (such as Pinus thunbergii, Pinus densiflora, Sorbus alnifolia, Albizzia julibrissin and etc.) and the additinal 7 species which are grown at a sprout cultivation palce of the SUDOKWON landfill site (Rosa rugosa, Quercus acutissima, Prunus armeniaca var. ansu., and etc.). Sub-trees with a height of above 2.5m and seedlings are planted with an interval of $1.5{\times}1.5m$ ($0.45roots/m^2$) and $0.5{\times}0.5m$ ($4roots/m^2$), respectively. Here, both trees exhibit communities planting with more than three rows. Shrubs are planted with $9-16roots/m^2$, depending on their size. Since this case study provides a reference of the planting beds as well as a planting plan at the SUDOKWON landfill site, it is not sufficient for the present plan to be utilized for the formation of buffer-forest belts which are used for the analysis of environmental factor and the reduction of environmental pollutants in the sea waste landfill site. Thus, further studies with the ecological basis are demanded for the environment planting restoration in the sea waste landfill site.