• 제목/요약/키워드: species richness

검색결과 698건 처리시간 0.024초

Community-level facilitation by macroalgal foundation species peaks at an intermediate level of environmental stress

  • Scrosati, Ricardo A.
    • ALGAE
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    • 제32권1호
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    • pp.41-46
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    • 2017
  • In rocky intertidal habitats, abiotic stress due to desiccation and thermal extremes increases with elevation because of tides. A study in Atlantic Canada showed that, at low elevations where conditions are benign due to the brief low tides, fucoid algal canopies (Ascophyllum nodosum and Fucus spp.) do not affect the structure of benthic communities. However, at middle and high elevations, where low tides last longer, fucoid canopies limit abiotic extremes and increase the richness (number of invertebrate and algal species, except fucoids) of benthic communities. Using the data from that study, this paper compares the intensity of facilitation and its importance (relative to all other sources of variation in richness) between middle and high elevations, which represent intermediate and high stress, respectively. Facilitation intensity was calculated as the percent increase in benthic richness between quadrats with low and high canopy cover, while the importance of facilitation was calculated as the percentage of variation in richness explained by canopy cover. Data for 689 quadrats spanning 350 km of coastline were used. Both the intensity and importance of facilitation were greater at middle elevations than at high elevations. As canopies do not affect benthic communities at low elevations, this study suggests that the facilitation-stress relationship at the community level is unimodal for this marine system. Such a pattern was found for some terrestrial systems dominated by canopy-forming plants. Thus, it might be ubiquitous in nature and, as further studies refine it, it might help to predict community-level facilitation depending on environmental stress.

Species Alterations Caused by Nitrogen and Carbon Addition in Nutrient-deficient Municipal Waste Landfills

  • Kim, Kee-Dae
    • Journal of Ecology and Environment
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    • 제30권2호
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    • pp.161-170
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    • 2007
  • The ultimate target of restoring waste landfills is revegetation. The most effective method for increasing species richness and biomass in nutrient limited waste landfills is the use of fertilizers. The aim of the present study was to investigate the effects of nitrogen fertilizer, and the addition of carbon through sawdust, sucrose and litter, on vegetation dynamics at a representative municipal waste landfill in South Korea: Kyongseodong. A total of 288 permanent plots $(0.25m^2)$ were established and treated with nitrogen fertilizer (5, 10 and $20Ng/m^2$), sawdust $(289g/m^2)$ sucrose $(222g/m^2)$ and litter $(222g/m^2)$. The aboveground biomass was significantly enhanced by nitrogen fertilizer at 5 and $10Ng/m^2$, compared with the control plots. The total cover of all plant species increased significantly on plots treated with 5 and $20Ng/m^2$, as well as on those treated with sawdust and sucrose, compared with the control plots. The higher species richness after nitrogen fertilization of 10 to $20Ng/m^2$, and the sawdust and sucrose treatment demonstrated that this was an appropriate restoration option for nutrient deficient waste landfills. This study demonstrated positive nutrient impacts on plant biomass and species richness, despite the fact that municipal waste landfills are ecosystems that are highly disturbed by anthropogenic and internal factors (landfill gas and leachate). Adequate N and C combined treatments will accelerate species succession (higher species richness and perennial increase) for restoration of waste landfills.

Diversity and distribution of invasive alien plant species along elevation gradient in Makawanpur district, central Nepal

  • Dipesh Karki;Bijay Pandeya;Balkrishna Ghimire
    • Journal of Ecology and Environment
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    • 제47권3호
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    • pp.75-84
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    • 2023
  • Background: Knowledge of the spatial trends of plant invasions in different habitats is essential for a better understanding of the process of these invasions. We examined the variation in invasive alien plant species (IAS) richness and composition at two spatial scales defined by elevation and habitat types (roadside, forest, and cultivated lands) in the Makawanpur district of Nepal. Following an elevation gradient ranging from 500 to 2,400 m asl along a mountain road, plant species cover was recorded within sample plots of size 10 m × 5 m. Systematic random sampling was adopted in every 100 m elevation intervals on three habitat types. Results: Altogether 18 invasive alien plants belonging to eight families were recorded within 60 plots, of which 14 species (representing 80%) were from tropical North and South America. The most common plants by their frequency were Ageratina adenophora, Chromolaena odorata, Bidens pilosa, Lantana camara, and Parthenium hysterophorus. We found a significant relationship between species composition and elevation in the study area. Low-elevation regions had a higher number of alien species as compared to high-elevation regions within different habitat types. Conclusions: The species richness and density of IAS were higher in the road site followed by the cultivated land and forest sites. This pattern occurred throughout the elevation range and habitats. IAS were found mostly in the open land with high sunlight availability. Information from such scientific assessment of invasive alien plants will assist in developing appropriate management plans in the Makawanpur district.

충남 광역생태네트워크 자연녹지의 훼손 인자 및 원인에 관한 연구 (A Study on Damage Factors and Causes of Natural Forest in Regional Ecological Network at Chungnam Province)

  • 이종문;조용현;김광동;이민우;김진기;최정권;김원태;윤충원;강희경
    • 한국환경복원기술학회지
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    • 제18권6호
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    • pp.97-110
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    • 2015
  • This study aimed to classify damaged lands, to find what are the damage factors affecting the studied area, and to present a prescription in order to provide some benefit for the restoration of Regional Ecological Network at Chungnam province. Finally we classified damaged lands from 1st to 4th damaged lands according to relative intensity of damage. The main damage factors for the First Damage Lands were humus horizon, soil hardness and plant species richness. In the Second Damage Lands, those were soil hardness, plant species richness, number of plants and dominant plant species. In the Third Damage Lands, those were humus horizon, soil hardness, plant species richness, number of plants and dominant plant species. In the Fourth Damage Lands, those were humus horizon, organic matter, soil hardness, EC, T-N content, plant species richness, number of plants and dominant plant species. In every cases, the damage of soil and vegetation was originated due to development carried out by human being. The changes in soil condition were not big enough for it to affect plant growth, however, degradation of vegetation was still severe.

Changes in Understory Vegetation of a Thinned Japanese Larch (Larix leptolepis) Plantation in Yangpyeong, Korea

  • Son, Yo-Whan;Lee, Yoon-Young;Kim, Rae-Hyun;Seo, Kyung-Won;Ban, Ji-Yeon;Seo, Kum-Young;Koo, Jin-Woo;Kyung, Ji-Hyun;Noh, Nam-Jin
    • The Korean Journal of Ecology
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    • 제27권6호
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    • pp.363-367
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    • 2004
  • Photosynthetically active radiation (PAR) beneath the forest canopy, understory species richness and diversity, and biomass were measured in a Larix leptolepis plantation seven years after thinning in Yangpyeong. Four different thinning intensities (control, $10\%,\;20\%\;and\;40\%$ stocking reduction) were applied in 1997. The current PAR values were lower than those measured four years after thinning, and PAR at the heavy thinning plots was significantly higher than that of other thinning intensities. A total of 23 species including 9 tall-trees and 14 shrubs were found for the high layer while a total of 82 species including 10 tall-trees, 29 shrubs, and 43 herbs for the low layer. Species richness and diversity generally increased with thinning intensities, and the trends were more evident for the low layer. Aboveground biomass significantly differed among thinning intensities for both shrubs and herbs. Also there was a negative correlation between biomass and the current number of stems per hectare. The current study suggested that the effects of thinning on light conditions at the forest floor, species richness and diversity and production of understory vegetation continued seven years after the treatment.

Soil Chemical Properties - Variation with Altitude and Forest Composition: A Case Study of Kedarnath Wildlife Sanctuary, Western Himalaya (India)

  • Malik, Zubair A.;Haq, Shiekh Marifatul
    • Journal of Forest and Environmental Science
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    • 제38권1호
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    • pp.21-37
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    • 2022
  • The present study was carried out to evaluate the chemical properties of soil in relation to forest structure and composition at different altitudes (900-2,600 m asl) in a part of Western Himalaya. The composite soil samples were taken from three (viz. upper, middle and lower) depths. The soils of the whole study area were acidic in nature (pH=4.90-5.51). Contents of Nitrogen (N), Phosphorus (P), Potassium (K), Carbon (C) and soil organic matter (SOM) showed much fluctuation during different seasons of year. Nitrogen content showed significant positive correlations with altitude (r=0.924, p<0.05) and different community parameters like species diversity (r=0.892, p<0.01) and species richness (r=0.941, p<0.05). Phosphorus exhibited direct correlations with carbon (r=0.637) while weak negative correlations with different community parameters like species richness & diversity, total basal cover (TBC), density and canopy cover. Carbon content and hence SOM showed direct correlations with Nitrogen (r=0.821, p<0.01); Phosphorus (r=0.637, ns) and Potassium (r=0.540, ns). But no significant relationship was observed between K content and species richness (p=0.30, r=-0.504); between K content and species diversity (p=0.14, r=-0.672); between P content and species diversity (p=0.29, r=-0.513) and species richness (p=0.23, r=-0.575). Among the different soil nutrients, only N showed a significant positive correlation with altitude while all others exhibited negative (but non-significant) correlation with it. The study revealed that the chemical properties affect and are reciprocally affected by forest structure and composition and that N rich soils of higher altitudes are best for the growth and development of forests.

점봉산 생물권 보전지역내 온대낙엽수림에서 미소환경요인과 식생요인의 공간분포와 상관 분석 (Relationships Between the Spatial Distribution of Vegetation and Microenviromnent in a Temperate Hardwood Forest in Mt. Jrnbong Biosphere Reserve Area, Korea)

  • 이규송;조도순
    • The Korean Journal of Ecology
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    • 제23권3호
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    • pp.241-253
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    • 2000
  • 생태계 내에서 미소환경요인과 식생 요인의 상호관련성을 밝히는 일은 생태계의 구성원리와 생태계의 관리에 많은 도움을 준다. 생물권보전지역으로 지정된 점봉산 일대의 온대낙엽수림에서 식생요인과 환경요인의 공간적 이질성을 정량화하고, 임상식생의 공간분포에 미치는 미소환경요인의 영향을 파악하였다. 대부분의 환경요인과 식생요인은 영구방형구내 미소지소간에 변이를 나타내었다. 환경요인 중에서 공간의존도가 높은 요인들은 지형적요인(고도, 경사도), 낙엽층 두께, 토양수분 함량 및 상대광도이었고, 공간의존거리가 상대적으로 짧은 요인은 낙엽층 두께, 상대광도 및 마그네슘 함량이었다. 식생요인 중에서 아교목층의 피도, 가을 초본층의 피도 및 철쭉꽃의 피도를 제외하고는 모든 변수들의 공간의존도는 높은 편이었다. 교목층의 피도, 관목층의 피도 및 가을 초본층의 종다양성 지수의 공간의존거리는 15 m 이내이었고,초봄 초본층의 종풍부도와 종다양성지수 및 가을 초본층의 종풍부도의 공간의존거리는 28∼48 m이었다. 초봄과 가을 임상식물의 종풍부도와 종다양성지수의 공간분포에 영향을 주는 요인으로는 낙엽층 두께, 경사도, 아교목층의 피도, 관목층의 피도, 조릿대의 피도 등이었는데,그 중에서 가장 크게 영향을 주는 요인은 낙엽층 두께로서 낙엽층 두께가 두꺼운 곳일수록 종풍부도와 종다양성지수가 낮은 경향이었다. 본 조사지역에서 낙엽층의 공간 분포에 영향을 주는 요인들로는 바람의 방향, 미소지형 및 관목의 밀집정도로 추정되었다.

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Differences in Moth Diversity in Two Types of Forest Patches in an Agricultural Landscape in Southern Korea - Effects of Habitat Heterogeneity -

  • Choi, Sei-Woong;Park, Marana;Kim, Hui
    • Journal of Ecology and Environment
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    • 제32권3호
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    • pp.183-189
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    • 2009
  • This research focused on the effects of fragmentation on moth diversity in an agricultural land-scape by comparing moth species richness and abundance between hillocks and young secondary forests. We examined five sites from the southwestern part of South Korea: three sites from hillock forest and two from secondary forest. We collected moths bi-weekly from April to October for a 2-year period (2006-2007) with a UV light trap that usually attracts moths within 30 meters. Tree species richness and abundance in $20m{\times}20m$ plots at each moth sampling site showed a substantial difference in tree diversity between the two types of forest habitats. The total abundance and richness of moth species were higher in secondary forests (541 species with 4,998 individuals) than in hillock forests (423 species with 3,913 individuals), irrespective of the distance among the sites. An ordination analysis with NMDS showed that habitat is the most important factor of grouping sites. The food preferences of the dominant moth species i,n each habitat were closely related to the habitat type.

남한지역 전통민속식물지식 자료를 활용한 종누적곡선 분석 및 종풍부도 추정 연구 (The Application of Species Richness Estimators and Species Accumulation Curves to Traditional Ethnobotanical Knowledges in South Korea)

  • 박유철;장계선;김휘
    • 한국자원식물학회지
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    • 제30권5호
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    • pp.481-488
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    • 2017
  • 전통민속식물지식이 빠르게 사라져 가는 상황에서 전통식물지식에 대한 기초조사를 통한 기록이 매우 중요한 과제가 되었다. 민속식물학 조사에서 조사강도와 민속식물정보, 식물종 정보의 증가에 관련성은 가장 중요한 과제이다. 본 연구에서는 국립수목원에서 발간된 자료를 이용하여 한반도 민속식물에 대한 메타 데이터를 DB화하여 분석하였다. 전통민속식물지식의 종풍부도에 추정은 ACE, Chao1, Chao 2, ICE, Jack 1, Jack 2, Bootstrap 등의 추정식을 이용하여 제시하였다. 종누적곡선 분석에서 지역별 종누적이 다른 양상을 보여 강원도의 누적곡선은 상대적 샘플링 노력이 더 필요하며충남 지역의 경우 조사 강도에 비해 일찍 수평선에 점근하는 특성을 보여 이지역의 조사 강도가 실제 정보량의 증가에 비해 높았다. 식용, 약용, 공예용 등의 종풍부도는 남녀간의 지식이 분포가 차이가 있음을 확인하였다. 주변환경의 식물상과 비교분석을 통해 일부 지역의 경우 민속식물조사가 상대적으로 조사량이 부족하고 추가 조사시 더 다양한 종이 발굴 될 것으로 예상된다.

Moth Fauna of Gageodo Island in the Southwestern Sea, Korean Peninsula, including Seven Unrecorded Species (Lepidoptera)

  • Choi, Sei-Woong;Kim, Sung-Soo;An, Jeong-Seop;Kwon, Tae-Sung
    • Animal Systematics, Evolution and Diversity
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    • 제31권4호
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    • pp.296-303
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    • 2015
  • We surveyed moths on Gageodo island in the southwestern sea of the Korean Peninsula over three years (2009, 2012, 2013) and found a total of 253 species in 18 families. Geometridae had the greatest species richness, with 63 species, followed by Noctuidae, Erebidae, Crambidae and Sphingidae. The annual changes in species richness and abundance were not different and seasonal occurrence of species showed a unimodal pattern in which the numbers of species and individuals increased from April and May, peaked in June and decreased to September and October. Seven moth species (Pyralidae: Herculia drabicilialis Yamanaka, Didia striatella (Inoue); Crambidae: Clupeosoma pryeri (Butler), Demobotys pervulgalis (Hampson), Yezobotys dissimilis (Yamanaka), Syllepte cissalis Yamanaka; Erebidae: Hypena sinuosa (Wileman)) are reported for the first time in Korea.