• 제목/요약/키워드: relative abundance

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Butterfly Diversity, Distribution, and Abundance in the University of Port Harcourt River State, Nigeria

  • Efenakpo, Ogaga Dean;Zakka, Usman;Omanoye, Dokubo ThankGod
    • Journal of Forest and Environmental Science
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    • 제37권3호
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    • pp.243-250
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    • 2021
  • Information on butterflies in the Niger Delta Region is relatively scanty because monitoring of their activities and distribution has not been fully documented and these are paramount to establish their conservation protocols. The study therefore aimed at evaluating the species richness distribution pattern, and relative abundance of butterflies in the University of Port Harcourt. The University Park was purposively selected for this study. The park was stratified into three different habitat types (secondary forest, farmland, and residential/garden). A sampling of each stratum was done three times; twice in the morning between 8:00 am and 12:00 pm as well as once in the evening between 4:00 pm and 6:00 pm along a 100 m line transects for 16 months (May 2017-August 2018). Data collected were analyzed for species diversity indices, evenness, and similarity index. A total of 1,932 individual butterflies belonging to 28 species, 18 genera, and five 5 families were identified in the study area. Species diversity and evenness were higher on farmland (1-D=0.909; H'=2.615; E=0.833), and least in the residential area/gardens (1-D=0.744; H'=1.975; E=0.659). The family Nymphalidae (39.0%) had the highest number of species occurrence while Hesperidae (0.4%) had the lowest composition. Anthene larydas (24.12%) had the highest relative abundance in the entire study area, followed by Acraea serena (17.49%). The study, therefore, recommends continuous monitoring of butterfly species diversity and composition also in other regions.

Identification of heat shock protein70-2 and protamine-1 mRNA, proteins, and analyses of their association with fertility using frozen-thawed sperm in Madura bulls

  • Zulfi Nur Amrina Rosyada;Berlin Pandapotan Pardede;Ekayanti Mulyawati Kaiin;Ligaya I.T.A Tumbelaka;Dedy Duryadi Solihin;Bambang Purwantara;Mokhamad Fakhrul Ulum
    • Animal Bioscience
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    • 제36권12호
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    • pp.1796-1805
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    • 2023
  • Objective: This study aims to identify heat shock protein70-2 (HSP70-2) and protamine-1 (PRM1) mRNA and protein in Madura bull sperm and demonstrate their relation as bull fertility biomarkers. Methods: The Madura bull fertility rates were grouped based on the percentage of first service conception rate (%FSCR) as high fertility (HF) (79.04%; n = 4), and low fertility (LF) (65.84%; n = 4). mRNA of HSP70-2 and PRM1 with peptidylprolyl isomerase A (PPIA) as a housekeeping gene were determined by quantitative real-time polymerase chain reaction, while enzyme-linked immunoassay was used to measure protein abundance. In the post-thawed semen samples, sperm motility, viability, acrosome integrity, and sperm DNA fragmentation index were analyzed. Data analysis was performed on the measured parameters of semen quality, relative mRNA expression, and protein abundance of HSP70-2 and PRM1, among the bulls with various fertility levels (HF and LF) in a one-way analysis of variance analysis. The Pearson correlation was used to analyze the relationship between semen quality, mRNA, proteins, and fertility rate. Results: Relative mRNA expression and protein abundance of HSP70-2 and PRM1 were detected and were found to be highly expressed in bulls with HF (p<0.05) and were associated with several parameters of semen quality. Conclusion: HSP70-2 and PRM1 mRNA and protein molecules have great potential to serve as molecular markers for determining bull fertility.

Terrestrial pest gastropod diversity and spatiotemporal variations in highland agricultural lands of Sri Lanka

  • Dinelka Thilakarathne;Nadeela Hirimuthugoda;Kithsiri Ranawana;Shalika Kumburegama
    • Journal of Ecology and Environment
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    • 제48권1호
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    • pp.60-73
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    • 2024
  • Background: The available information on terrestrial pest gastropods and their impact on the environment worldwide is scarce and outdated. The present study aimed to address this gap by conducting the first comprehensive survey of pest gastropods in the Nuwara Eliya District, an important vegetable growing area in the highlands of Sri Lanka. Eighty agricultural lands were surveyed over two years by establishing ten 1 m2 sampling plots per crop type in each agricultural land. Geo-coordinates, air temperature, elevation, relative humidity, daily rainfall, soil pH, species richness and abundance were recorded for rainy and non-rainy periods. The relationship between species composition and environmental variables was analyzed using multi-regression models and distribution maps. Results: Out of the 14 species recorded in agricultural lands, nine were identified as exotic pest species. Species abundance (t = 4.69, p < 0.05) and diversity was higher in the rainy period and the dominant species during this period were Bradybaena similaris (t = 2.69, p < 0.05) and Deroceras reticulatum (t = 2. 46, p < 0.05). Eggs and estivating adults were found in soil and under decaying organic matter during the non-rainy period. The exotic species showed broader preferences for the measured environmental factors and showed a wider range in distribution compared to the native species. Variation in pest gastropod composition was significantly accounted for by elevation, relative humidity, soil pH and daily rainfall. Additionally, the species richness and abundance varied across locations due to the combined effects of elevation, crop type and stage, and field type. Conclusions: The study emphasizes the importance of understanding the biology and ecology of gastropod pests to develop effective management strategies. By considering the influence of environmental factors and implementing appropriate soil management techniques, such as targeting specific habitats and crop stages, it is possible to mitigate pest populations and minimize their impact on agricultural lands. Overall, this research contributes valuable insights into the dynamics and interactions of terrestrial gastropods in agricultural ecosystems, supporting sustainable pest management practices.

Spatial Abundance and Diversity of Bacterioplankton in a Typical Stream-Forming Ecosystem, Huangqian Reservoir, China

  • Wei, Guangshan;Li, Jing;Wang, Ningxin;Gao, Zheng
    • Journal of Microbiology and Biotechnology
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    • 제24권10호
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    • pp.1308-1318
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    • 2014
  • The specific freshwater environment of reservoirs formed by streams has not been well studied. In this paper, the bacterioplankton community in such a reservoir, the Huangqian Reservoir in eastern China, was described using culture-independent molecular methods. We found that the most dominant bacterioplankton were affiliated with Cyanobacteria, followed by Betaproteobacteria, Bacteroidetes, Gammaproteobacteria, and Actinobacteria. Both bacterial abundance and diversity increased along the direction of water flow, and the 16S rRNA gene copy number in the water outlet was nearly an order of magnitude higher than that in the water inlet. Pearson correlation analyses indicated that nitrate had a significantly negative correlation with the bacterial abundance (p < 0.05) and that ammonium was positively correlated with bacterial abundance (p < 0.05). Interestingly, owing to a remarkably negative correlation (p < 0.01), the ratio of nitrate and ammonium might serve as a good pre dictor of the relative abundance of bacterioplankton. According to redundancy analysis, nitrate and dissolved oxygen were the major factors influencing the bacterial communities. In addition, we attempted to determine the reasons why such a reservoir could maintain good ecological balance for a period of decades, and we found that the environmental factors and bacterial communities both played critical roles. This research will benefit our understanding of bacterial communities and their surrounding environments in freshwater ecosystems.

Methodological Study on Measurement of Hydrogen Abundance in Hydrogen Isotopes System by Low Resolution Mass Spectrometry

  • Lia, Jin-Ying;Shib, Lei;Hub, Shi-Lin
    • Mass Spectrometry Letters
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    • 제2권1호
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    • pp.1-7
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    • 2011
  • China's rapid economic growth has resulted in significant environmental side effects. Therefore, China has been interested in reducing her dependence on foreign oil and gas by developing technologies needed for hydrogen, in addition to her increasing energy mix of nuclear and renewable energy form, such as solar and wind power. There are three isotopes of hydrogen, i.e. protium (P or H), deuterium (D), and tritium (T). Both deuterium and tritium are important materials in nuclear fuel cycle industry. Tritium is one of the critical radioactive nuclides. Planning for and implementing contamination control as a part of normal operation and maintenance activities is an important function in any hydrogen facility, especially tritium facility. The development of hydrogen isotopes analysis is the key issues in this area. Mass spectrometry (MS) with medium (about 600) and high resolution (> 1,400) is commercially available; however, the routine analysis of hydrogen isotopes is done with low-resolution MS (< 200) in China. This paper summarizes the progress of MS measurement technology for hydrogen isotope abundance in China, focusing on our lab's research program and technical status. An analyzing method has been introduced for accurate measurement of tritium abundance in the H.D.T system by low resolution MAT-253 MS. The quotient of compression ratio coefficient is determined by building up equipment for laboratory-scale preparation of secondary standard gases and by considering the difference in sensitivity between hydrogen isotopes. The results show that the measured value is reproducible within the relative error range of 0.8% for gas samples of different tritium abundance.

국내 중대형 인공호에서 외래종인 배스(Micropterus salmoides)의 분포 특성 및 서식지의 이화학적 수질 (Distribution Characteristics of Largemouth Bass (Micropterus salmoides) as an Exotic Species, in Some Medium-to-Large Size Korean Reservoirs and Physico-chemical Water Quality in the Habitats)

  • 김현맥;길지현;이의행;안광국
    • 생태와환경
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    • 제46권4호
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    • pp.541-550
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    • 2013
  • 본 연구에서는 2011년 우리나라 10개의 중대형 인공호에서 배스의 우점도에 의한 외래종 영향 및 이에 대한 어류 군집 구조 분석을 실시하였고, 이들이 출현하는 호수에 대한 이화학적 수질특성을 분석하였다. 10개 인공호에서 출현한 어류는 13과 52종이었으며, 배스의 상대 풍부도는 전체 어종들 중 13%를 차지하여, 출현한 어류들 중 3번째로 높게 우점하는 것으로 나타났다. 이런 결과는 향후 배스가 수체내에서 최상위 포식자로서의 포식압 및 생태적 지위 특성 때문에 많은 인공호들에서는 본 배스의 외래종 번성에 의한 생태계 교란 효과가 극대화 될 수 있음을 제시하였다. 전체 조사 대상 인공호들 중 평택호에서 배스의 상대 풍부도는 60%로서 가장 높게 나타난 반면, 대청호에서 풍부도는 3%로서 가장 낮게 나타났다. 배스 서식지에 대한 이 화학적 수질분석 결과에 따르면, COD는 평균 $4.5{\pm}2.5mgL^{-1}$였고, 총인 (TP) 농도는 $0.058{\pm}0.047mgL^{-1}$, 총질소(TN)는 $2.2{\pm}1.4mgL^{-1}$로 나타났다. 인 (P)과 질소(N)의 농도 분석에 따르면, 평택호, 낙동강하구언, 주남저수지 등의 수체는 부영양화 현상이 높은 것으로 나타났다. 배스의 상대풍부도와 수질자료의 비교분석에 따르면, 두 변수는 통계학적으로 유의한 상관관계 (p>0.05)를 보이지 않았다. 즉, 배스의 분포 및 풍부도 특성은 이화학적 수질도 중요하겠지만, 이들보다는 여러 타 요인들, 즉, 물리적 서식지 특성, 이용 가능한 먹이양 및 경쟁생물의 밀도 등에 의해 더 영향 받을 것으로 추정되었다.

동해 축산항 연안의 식물플랑크톤 군집 동태 (Dynamics of the Phytoplankton Community in the Coastal Waters of Chuksan Harbor, East Sea)

  • 강연식;최휴창;임주환;전인성;서지호
    • ALGAE
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    • 제20권4호
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    • pp.345-352
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    • 2005
  • In order to investigate the distribution of phytoplankton community in the coastal waters of the Chuksan Harbor, East Sea, the abundance and biomass of phytoplankton have been evaluated through seasonal interval sampling from April 2000 to October 2002. A total of 363 different phytoplankton species was observed and most of them were composed of diatoms. The mean abundance and chlorophyll-a concentration of phytoplankton during the study period ranged from 56 ${\times}$ $10^3$ to 720 ${\times}$ $10^3$ cells $L^{-1}$ and from 0.78 to 3.29 μg chl-a $L^{-1}$, respectively. The relative contribution of the size-fractionated phytoplankton to phytoplankton community showed difference according to seasons. The average contribution of nano-phytoplankton(<20 $\mu$m) was over 50% in the total abundance and biomass of the phytoplankton. Our results show that nano-phytoplankton play an important role in the southern coastal waters of the East Sea. And the environmental factors such as suspended substances, phosphates and silicates were positively correlated with the abundances and biomass of phytoplankton.

The clonal seaweed Chondrus crispus as a foundation species

  • Scrosati, Ricardo A.
    • ALGAE
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    • 제31권1호
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    • pp.41-48
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    • 2016
  • The clonal seaweed Chondrus crispus (Rhodophyta, Gigartinales) forms extensive stands at low intertidal elevations on wave-sheltered rocky shores of the North Atlantic. This study investigates if this bushy alga acts as a foundation species in such habitats. The abundance (percent cover) of C. crispus, all other algae, and invertebrates was measured in 390 quadrats spanning 350 km of coast in Nova Scotia, Canada. In these low-intertidal habitats, fucoid algae are the largest organisms and can form extensive canopies, but their cover was unrelated to benthic species richness and to C. crispus cover. Species richness, however, increased with C. crispus cover from low to intermediate cover values, showing little change towards full C. crispus cover. Species composition (a combined measure of species identity and their relative abundance) differed between quadrats with low (0-1%) and high (60-100%) cover of C. crispus. High C. crispus cover was associated to more invertebrate species but fewer algal species than low C. crispus cover. However, the average abundance of algal and invertebrate species occurring in both cover groups was often higher under high C. crispus cover, contributing to a higher average richness at the quadrat scale. Overall, only 16% of the observed variation in species richness was explained by C. crispus cover. Therefore, this study suggests that C. crispus acts as a foundation species but with a moderate influence.

조간대 감습지 수로지역의 저생조류의 종조성 및 일차생산 (Species Composition and Primary Production of the Benthic Algal Assemblage along a Channel in Salt Marsh, Kyonggi Bay, Korea)

  • Cho, Kyung Je;Joon Ho Kim
    • The Korean Journal of Ecology
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    • 제11권1호
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    • pp.1-15
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    • 1988
  • Studies on species compostion, promary production of benthic algal assemblage were carried out along a channel of the salt marsh near Inch'on, Kyonggi Bay, Korea. Possible biological, physical and KDICical factors controlling the aglal assemblage were also examined. The oveall diatoms were encountered one hundred and thirty-seven taxa, of which the dominant species were Paralia sulcata and Cymatosira belgica. These two species accounted for 32.6% relative abundance throughout the study period. Diatom taxa had no clear seasonal pattern in abundance analysis. But at the algal blooming period in spring, euglenoids occurred with a high abundance. The chlorophyll a content of benthic algae showed definite seasonal pattern. The algal biomass of the appeared to influence the spatial fluctuation in the algal biomass of the channel was regulated primarily by water content of sediment. Grazing by zoobenthos apperaed to influence the spatial fluctuation in the algal biomass of the sediment surface. The algal photosynthesis was measured in the laboratory with oxygen method. Photo-synthetic rate was independent of the temperature under the lower irradiance. The gross production from March to November was estimated to be 190g C/m2 at the channel slope. Photosynthetic efficiency was 0.37% on the basis of the photosyntherically active radiation for the study period.

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Observations of the CH3OH 42-51 E Line Toward the Sgr B2 Region

  • Minh, Young-Chol;Kim, Sang-Joon
    • Journal of Astronomy and Space Sciences
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    • 제28권1호
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    • pp.13-16
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    • 2011
  • The $CH_3OH$ $4_2-5_1$ E transition was observed toward the Sgr B2 region, including the Principal Cloud and its surroundings. This methanol transition shows an extended emission along the 2'N cloud, which is believed to be colliding with the Principal Cloud and may trigger the massive star formation in this cloud. This extended methanol emission may also suggest that the 2'N cloud is under shocks. We derive total methanol column density $N(CH_3OH)\;=\;2.9{\pm}0.3{\times}10^{14}\;cm^{-2}$ toward the peak position of the extended emission. The fractional abundance of methanol is about 10.9, relative to the estimated total $H_2$ abundance, which is similar to the methanol abundances in quiet gas phase.