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OLUWATOBI, Ayodele Samuel, and Kehinde Stephen OLORUNMAIYE. "Weed Species Distribution of Juvenile Oil Palm Tree (Elaeis guineensis) Intercropped with Maize (Zea mays), Okra (Abelmoshus esculentus) and Pepper (Capsicum anuum var. abbreviatum)." Notulae Scientia Biologicae 6, no. 4 (December 8, 2014): 483–90. http://dx.doi.org/10.15835/nsb649358.
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This field experiment was carried out to evaluate the weed species distribution in the experimental plots of an intercrop of juvenile oil palm trees (Elaeis guineensis Jacq.) with maize (Zea mays Linn.), okra (Abelmoschus esculentus Moench) and pepper (Capsicum annuum var. abbreviatum). This was carried out during the cropping season between July and October 2012. The crops were intercropped with the juvenile oil palm trees of about 3-years-old. The experiment was laid out in a completely randomized block design with five (5) replicates. The treatments comprised of intercropping distances of 1 m, 2 m and 3 m each for the three (3) crops (maize, okra and pepper) and a plot for each of the three (3) arable crops without oil palm trees as control. Weed species distribution was carried out in each of the plots to determine the Simpson’s Diversity Index (D), Simpson’s Index of Diversity (1-D) and Simpson’s Reciprocal Index (1/D). Weed species’ frequency, density, relative density, relative frequency, importance value, abundance, dominance and relative dominance were also computed from data collected at 3WAP and 6WAP. The results showed that the control plot has the highest weed species distribution at 3WAP having the lowest Simpson’s Diversity Index (D) of 0.0930. Okra plot has the least weed species distribution with the highest Simpson’s Diversity Index (D) of 0.2726. At 6WAP, the pepper plot has the highest weed species distribution having the lowest Simpson’s Diversity Index (D) of 0.1741. Control plot has the least weed species distribution with highest Simpson’s Diversity Index (D) of 0.2831.
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Lipovetsky, Stan, and W. Michael Conklin. "Data aggregation and Simpson’s paradox gauged by index numbers." European Journal of Operational Research 172, no. 1 (July 2006): 334–51. http://dx.doi.org/10.1016/j.ejor.2004.10.005.
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Sivaruban, T., S. Barathy, Pandiarajan Srinivasan, Rajasekaran Isack, and Bernath Rosi. "Impact of ecological attributes and feeding categorization of Ephemeroptera, Plecoptera and Trichoptera (EPT) insects in Kiliyur falls of Eastern Ghats, India." ENTOMON 45, no. 3 (September 30, 2020): 171–80. http://dx.doi.org/10.33307/entomon.v45i3.548.
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Investigation on the diversity, ecology and trophic categorization of Ephemeroptera, Plecoptera and Trichoptera complex (EPT) was carried out in Kiliyur falls of the Eastern Ghats. An aggregate of 2,189 specimens belonging to 24 genera, 12 families and 3 orders were collected. Ephemeroptera was found to be high when compared to Plecoptera and Trichoptera. Baetidae was the most abundant taxa of all with presence of 5 genera and 6 species. Shannon-Weiner index and Simpson’s index were calculated and it shows that Shannon-Weiner index was elevated in the August (2.882) and declines in January (2.744). Simpson’s index was most noteworthy in December (0.9325) and it was least in January (0.9321). Canonical correlation analysis (CCA) shows that temperature, dissolved oxygen and rainfall turns into a major stressor in the EPT community of Kiliyur falls. Cluster analysis results prove that Baetidae and Caenidae shows comparative dispersion pattern as opposed to Teloganodidae and Perlidae. Functional feeding group (FFG) analysis shows that Kiliyur stream was overwhelmed by collectors followed by scrapers, predators and filter-feeders.
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Raus, Josef, Pavel Knot, Jiří Skládanka, Michal Kvasnovský, Martin Sochorec, Jhonny Edison Alba Mejía, and František Hrabě. "Effect of Cutting Pattern and Fertilization Level on Species Diversity and Evaluation of Grassland Quality." Acta Universitatis Agriculturae et Silviculturae Mendelianae Brunensis 62, no. 5 (2014): 1087–93. http://dx.doi.org/10.11118/actaun201462051087.
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The effects of fertilization level and cutting pattern on the species diversity and quality of a meadow stand were assessed in 2004–2012 in the small plot trial established in 2003 in Vatín, Vysočina Region, Czech Republic. Four levels of fertilization (none; N0 + P30 + K60 kg∙ha−1; N90 + P30 + K60 kg∙ha−1; N180 + P30 + K60 kg∙ha−1) were combined with four treatments of exploitation intensity (4 cuts per year, first cut on 15th May, every next after 45 days; 3 cuts per year, first cut on 30th May, every next after 60 days; 2 cuts per year, first cut on 15th June, next after 90 days; 2 cuts per year, first cut on 30th June, next after 90 days). Numbers of species, Simpson’s diversity index and evaluation of grassland quality according to Novák (2004) were evaluated. Numbers of species and Simpson’s diversity index were significantly affected by both fertilization level and cutting pattern. Species richness decreased along with increasing fertilization rates from 29.4 (no fertilization) to 27.8 (N180PK). When comparing cutting pattern treatments the highest species richness was found in four-cut swards (29.6 in average of fertilization levels) and it declines towards late double-cut regime (27.2). The Simpson’s index generally increased from two-cut swards to four-cut and from fertilized treatments to control. Grassland quality was significantly affected by cutting pattern. Values increased from four-cut swards (38.1) to two-cut ones (43.8 and 44.0 in early and late harvest respectively).
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Tweedley, James R., Chris S. Hallett, Richard M. Warwick, K. Robert Clarke, and Ian C. Potter. "The hypoxia that developed in a microtidal estuary following an extreme storm produced dramatic changes in the benthos." Marine and Freshwater Research 67, no. 3 (2016): 327. http://dx.doi.org/10.1071/mf14216.
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Runoff from an extreme storm on 22 March 2010 led, during the next 3 months, to the formation of a pronounced halocline and underlying hypoxia in the upper reaches of the microtidal Swan–Canning Estuary. Benthic macroinvertebrates were sampled between January 2010 and October 2011 at five sites along 10km of this region. By mid-April, the number of species, total density, Simpson’s evenness index and taxonomic distinctness had declined markedly, crustaceans had disappeared and the densities of annelids and molluscs had declined slightly. These faunal attributes (except Simpson’s index) and species composition did not recover until after the end of the hypoxia. The survival of annelids and loss of crustaceans in this period reflects different sensitivities of these taxa to severe environmental stress. The results emphasise that microtidal estuaries with long residence times are highly vulnerable to the effects of environmental perturbations, particularly during warmer periods of the year.
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Ługowska, Maria, and Zofia Rzymowska. "The effect of the application of the exact and approximate methods on values of selected ecological indices." Acta Agrobotanica 67, no. 1 (2014): 39–46. http://dx.doi.org/10.5586/aa.2014.011.
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<p>The work presents the results of a study on the biodiversity of agrocenoses using ecological indices. In order to calculate the measures, phytosociological relevés were made and exact methods were applied in winter cereals, spring cereals, tuber crops and stubble fields. The objective of the work was to compare ecological indices (Simpson’s index of dominance <em>C</em>, Simpson’s index of species richness <em>D,</em> and Shannon-Wiener index of biodiversity <em>H</em>’) calculated using the number of plants and their cover determined based on the degree of presence. Moreover, correlation analysis was conducted between the indices computed using the two approaches applied.</p><p>The results of the study revealed significant differences between all the indices calculated using the exact and approximate methods. In turn, comparisons of the measures computed for individual crops showed significant differences only for potato crops and winter cereals. No significant differences were found between the indicators calculated for spring cereals and stubble fields.</p>
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Dienye, Henry Eyina, Olaniyi Alaba Olopade, and Ike Joel Ogbonnaya. "Diversity and abundance of the family mugilidae in the New Calabar River, Nigeria." Vol:36 Issue:3 36, no. 3 (September 15, 2019): 313–18. http://dx.doi.org/10.12714/egejfas.2019.36.3.12.
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The study was conducted to determine the diversity and abundance of mullets (Mugilidae) in the New Calabar River, Nigeria. Fish samples were collected monthly between February to July 2018 at three landing stations: Choba: Station 1, Ogbogoro: Station 2 and Iwofe: Station 3. A total of 578 individuals belonging to three species (Sicklefin mullet (Neochelon falcipinnis Valenciennes, 1836), Largescaled mullet (Parachelon grandisquamis Valenciennes, 1836) and Flathead grey mullet (Mugil cephalus Linnaeus, 1758) of the family Mugilidae were sampled. N.falcipinus recorded the highest abundance (47.40%) followed by M.cephalus (36.85%) while P.grandisquamis recorded the least abundant (15.74%). The Simpson’s index of diversity had the highest value of 0.63 in Choba station and the least value of 0.59 in Iwofe station, while the Simpson’s reciprocal index highest value of 1.71 in Iwofe station and least value of 1.60 in Choba station. The Shannon- Weiner index and Pielou’s eveness index value also recorded highest values of 1.03 and 0.94 in Choba station with the least values of 0.96 and 0.87 in Iwofe station respectively. The diversity indices showed that the family Mugilidae is fairly distributed in the study area and it is therefore recommended that further research should be carried out to provide a complete examination of the biology and ecology of the mullets within the New Calabar River.
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Coelho, Mariana R., Ruthnea A. L. Muzzi, Elaine M. S. Dorneles, Guilherme G. Pereira, Rosa M. Cabral, Leonardo A. L. Muzzi, Claudine B. Abreu, and Luiz E. D. Oliveira. "Evaluation of left atrial function in asymptomatic dogs with chronic myxomatous mitral valve disease: two-dimensional feature-tracking echocardiography and Simpson’s monoplanar methods." Pesquisa Veterinária Brasileira 40, no. 3 (March 2020): 188–96. http://dx.doi.org/10.1590/1678-5150-pvb-6441.
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ABSTRACT: The present study evaluated the volume and function of the left atrium by two-dimensional echocardiographic feature-tracking imaging (2D-FTI) and Simpson’s monoplanar modeling in dogs with asymptomatic degenerative mitral valve disease (DMVD). The study consisted of 80 dogs that were divided into the following three groups: Group 1, 21 dogs (A); Group 2, 30 dogs (B1) and Group 3, 29 dogs (B2). The variable strain (contraction phase) was significantly lower in Group 3 than in Group 1 (12.92±4.54 x 16.69±5.74, p=0.014), and significant differences in the contraction strain index (CSI) were observed between all of the groups that were evaluated (1 = 46.82±8.10, 2 = 39.88±8.03, 3 = 35.25±5.64, p<0.0001). The atrial diastolic volume index (AdVi) that was measured by 2D-FTI was significantly higher in Group 3 than in Group 1 (1.31±0.95 x 0.96±0.31, p=0.038), and the atrial cardiac index (ACI) was also higher in Group 3 than in Group 1 (102.38±80.18 x 78.19±33.38, p=0.030). Atrial function was assessed by Simpson’s monoplanar method, which demonstrated an increase in the left atrial systolic volume, while the contractile function decreased with an increasing disease severity (Group 1 0.21±0.06; Group 2 0.25±0.06; Group 3 0.32±0.08, p<0.0001). The intraobserver and interobserver assessments showed low to moderate variability; most of the values for the coefficient of variation for the variables that were analysed with each method were below 25%. Thus, DMVD was determined to cause an alteration in atrial function, especially in the contraction phase, and even in asymptomatic animals, and the methods of 2D-FTI echocardiography and Simpson’s monoplanar evaluation are sensitive and early methods for the detection of left atrial dysfunction.
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Syiem, Mayashree B., B. Bashisha Nongbri, A. Pinokiyo, Amrita Bhattacharjee, Natasha A. Nongrum, and Luxemburgh Hynniewta. "Significance of cyanobacterial diversity in different ecological conditions of Meghalaya, India." Journal of Applied and Natural Science 2, no. 1 (June 1, 2010): 134–39. http://dx.doi.org/10.31018/jans.v2i1.112.
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The present study deals with preliminary investigation of cyanobacterial diversity in Meghalaya. A total of 75 samples were collected from 10 different ecosystems and analyzed. 65 strains of cyanobacteria isolated under 11 genera include Nostoc, Anabaena, Calothrix, Cylindrospermum, Gleocapsa, Fischerella, Plectonema, Tolypothrix, Stigonema, Loriella and Westiellopsis. Nostoc was most abundant. Diversity analysis indicated maximum Shannon’s diversity index (H) in Mawlai. Highest Simpson’s diversity index was seen in Sung Valley (0.75). Both Shannon’s and Simpson’s diversity indices were lowest in Mairang. Richness was highest in Sung valley and Syntuksiar with both the sites supporting 17 strains each. Although, highest diversity was recorded from Mawlai, richness recorded at this site was only 11 strains thereby indicating richness need not be a function of diversity in this region. This study revealed the cyanobacterial strains, which can withstand acidic pH and prevail in the region. A study on colonization also identified some potential biofertilizer strains from the region such as Nostoc punctiforme, Nostoc muscurum and Anabaena azollae that could be effective in acidic crop fields.
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Dienye, HE, OA Olopade, and SA Toby. "Species composition and diversity of cast net fisheries in New Calabar River, Niger Delta, Nigeria." Journal of Biodiversity Conservation and Bioresource Management 4, no. 1 (August 18, 2018): 19–26. http://dx.doi.org/10.3329/jbcbm.v4i1.37873.
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A study on the catch composition and diversity of cast net fisheries was conducted between May and August, 2017 in the New Calabar River, Rivers state, using cast net of varying mesh sizes (1.5mm and 2.5mm). Fish samples were collected from three sampling stations, viz. Station1- Aluu, Station 2- Choba and Station 3- Iwofe. The fish species recorded comprised of 26 species under 11 families, and one decapod crustacean. The three most abundant species were; Coptodon guineensis (25.11%), Coptodon zilli (18.56%) both from the Cichlidae family, and Penaeus nitialis (10.90%) from the Penaeidae family, while the least abundant species was Liza grandisquamis (0.13%) from the Mugilidae family. The diversity indices showed that station 2 recorded the highest number of species (21) while station 1 recorded the lowest with (12) species. Simpson’s indexes of diversity, Simpson’s reciprocal index, Shannon- weiner index, and Pielou’s evenness index, were estimated. This study serves as a base line data which will assist relevant bodies in the management and conservation of fisheries resources in the New Calabar River. It is therefore recommended that for an improved and sustainable exploitation and management of fisheries resources of the New Calabar River, proper monitoring and management for fish stock must be done.J. Biodivers. Conserv. Bioresour. Manag. 2018, 4(1): 19-26
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Berbeć, Adam Kleofas, Mariola Staniak, Beata Feledyn-Szewczyk, Anna Kocira, and Jarosław Stalenga. "Organic but Also Low-Input Conventional Farming Systems Support High Biodiversity of Weed Species in Winter Cereals." Agriculture 10, no. 9 (September 18, 2020): 413. http://dx.doi.org/10.3390/agriculture10090413.
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In recent years, the European Union has been paying particular attention to the problem of biodiversity loss. The possibilities of its assessment and conservation are included in the latest European Union (EU) policies and reflected in the European Biodiversity Strategy. The biodiversity of weeds in winter cereals in organic and conventional low-input farms in Eastern Poland was investigated during a 3-year period. Significantly more species and larger abundance were found in organic than in conventional farming systems. The biodiversity of these communities was described by Shannon’s diversity and Simpson’s dominance indices, which showed diversity to be well maintained in both farming systems; however, significantly higher Shannon’s index and significantly lower Simpson’s index values were observed in organic farms. Both farming systems were the mainstay of endangered and rare species, as well as some invasive weed species. Weed communities of organic farms were dominated mostly by Setaria pumila and Elymus repens, while conventional farms were dominated by Juncus bufonius and Setaria pumila. The study showed the importance of organic farming systems for biodiversity conservation. It was also shown that low-input (traditional) conventional farms are also beneficial for biodiversity conservation.
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Catling, Paul M., Brenda Kostiuk, and Don Thompson. "Horse ranching increases biodiversity in a foothills parkland prairie in northern Kananaskis Country, western Alberta." Canadian Field-Naturalist 129, no. 1 (May 31, 2015): 15. http://dx.doi.org/10.22621/cfn.v129i1.1663.
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Vascular plant biodiversity was evaluated in two adjacent sections of a continuous prairie glade. One section has been subject to moderate grazing by feral horses (Equus ferus caballus) in late summer and fall for the past 25 years, while the other has been protected. From 28 June to 2 July 2009, we recorded cover for all vascular plants present in ten 1-m2 quadrats along five transects in each section. We calculated biodiversity measures, including species richness, evenness, and Shannon-Wiener and Simpson’s diversity indexes. Horse grazing did not affect richness but significantly increased evenness. Grazing increased the Shannon-Wiener index, but did not affect the Simpson’s index. Cover and frequency values for most species differed significantly between the two sites. Mountain Rough Fescue (Festuca campestris Rydberg) dominated the non-grazed site but several shorter grasses and different forbs dominated the grazed site. The plant community in the grazed areas can be seen as an earlier seral stage of the fescue community with a different contingent of plant species. Light grazing in part of the prairie glade increased overall plant diversity so that it provided more diverse animal habitat.
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Pawlonka, Zbigniew, Katarzyna Rymuza, Krzysztof Starczewski, and Antoni Bombik. "Biodiversity of Segetal Weed Communities when Chlorsulfuron-Based Weed Control is Being Used on Continuous Winter Wheat." Journal of Plant Protection Research 54, no. 3 (July 1, 2014): 300–305. http://dx.doi.org/10.2478/jppr-2014-0045.
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Abstract The purpose of the study was to determine the relationship between herbicide rate and weed community biodiversity in continuous wheat. A six-year field experiment was conducted to examine the effect of four chlorsulfuron rates in comparison with untreated (the control) plots, on the status and severity of weed infestation - in successive study years of cultivating winter wheat in monoculture. In addition, the following indices were calculated: Shannon-Wiener and Simpson’s index of biodiversity, and Simpson’s index of domination. A total of 36 weedy species were identified in the experimental plots. The richest segetal communities were established in the control plots. An application of herbicide reduced the biodiversity of the agrophytocensosis. A short-term monoculture did not impoverish the species richness of the weed community established in winter wheat. The average number of species in the community was significantly greater in the second study year. In the initial study years of monoculture, the biodiversity of the segetal community increased markedly compared with rotation-based cultivation. The calculated indices of biodiversity were not significantly affected by herbicide rate or monoculture but the indices confirmed the trends outlined by an analysis of the status and level of weed infestation.
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Pawlonka, Zbigniew, Katarzyna Rymuza, Krzysztof Starczewski, and Antoni Bombik. "Biodiversity of segetal weed community in continuous potato cultivated with metribuzin-based weed control." Journal of Plant Protection Research 55, no. 1 (January 1, 2015): 52–57. http://dx.doi.org/10.1515/jppr-2015-0008.
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Abstract The objective of the work reported here was to determine the relationship between herbicide rate and the biodiversity of weed communities in potato cultivated in continuous cropping. A seven-year field experiment was conducted to examine the effect of 4 metribuzin rates and an uncontrol on weed infestation in successive years of continuous potato cultivation. The following indices were calculated: the Shannon-Wiener and Simpson’s indices of species diversity and the Simpson’s index of domination. A total of 33 species were recorded in the experimental plots. Echinochoa crus-galli was the dominant species. The most abundant segetal communities were observed in untreated plots. An application of the herbicide reduced the biodiversity of the agrophytocenosis. Cultivation in continuous cropping increased the species number of the weed community in potato. The herbicide and cultivation in continuous cropping did not significantly affect the biodiversity indices but their values, to a great extent, confirmed the trends revealed by the analysis of weed infestation
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McLaughlin, Jacqueline E., Gerald W. McLaughlin, Josetta S. McLaughlin, and Carla Y. White. "Using Simpson’s diversity index to examine multidimensional models of diversity in health professions education." International Journal of Medical Education 7 (January 3, 2016): 1–5. http://dx.doi.org/10.5116/ijme.565e.1112.
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SETIAWAN, YOGO, RINA RACHMAWATI, and HAGUS TARNO. "Diversity of ambrosia beetles (Coleoptera: Scolytidae) on teak forest in Malang District, East Java, Indonesia." Biodiversitas Journal of Biological Diversity 19, no. 5 (September 21, 2018): 1791–97. http://dx.doi.org/10.13057/biodiv/d190529.
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Setiawan Y, Rachmawati R, Tarno H. 2018. Diversity of ambrosia beetles (Coleoptera: Scolytidae) on teak forest in Malang District, East Java, Indonesia. Biodiversitas 19: 1791-1797. Ambrosia beetle plays an important role in the temperate forest. Ambrosia beetle lives symbiotically with microorganism such as fungi, bacterium, and yeast that can cause plant wilt and death. In Java, ambrosia beetle has been reported to attack teak plantations in some regions. This research aimed to investigate the diversity of ambrosia beetles in the teak plant on monoculture and polyculture system in Malang District. This research was conducted in the teak forest in Dampit and Sumbermanjing Wetan, Malang District from March to May 2017. Ambrosia beetles were trapped by using baited bottle trap with 95% ethanol. The diversity of ambrosia beetles trapped was analyzed using Vegan package in R program to calculate the Shannon-Wiener diversity index (H), Species Evenness index (E), and Simpson's dominance index (D). The results showed that ambrosia beetles trapped in monoculture and polyculture teak plants system consist of nine species, i.e., Xylosandrus crassiusculus, X. morigerus, X. compactus, Xyleborus perforans, Euwallacea simillis, Xyleborinus andrewesi, Premnobius cavipennis, Coccotrypes distinctus, and Hypothenemus hampei. The Shannon Wiener index of Ambrosia beetles in polyculture (H=1.40) was higher than in monoculture (H=1.30), and both locations were categorized in the medium diversity category. The Species Evenness index of ambrosia beetles in polyculture (E=0.67) and monoculture (E=0.66) were also categorized in medium category. The Simpson’s dominance index in both locations was categorized in the middle dominance species. X. crassiusculus was the dominant species in polyculture and monoculture teak plant system.
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Sarkar, Chandan, and Nimai Chandra Saha. "Seasonal Variation of Water Quality Parameters and Their Impact on Fish Biodiversity Indices of Hasadanga Beel: A Case Study." Current Research in Nutrition and Food Science Journal 16, no. 1 (April 28, 2021): 07–17. http://dx.doi.org/10.12944/cwe.16.1.03.
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Fish diversity indices and their correlation with seasonal fluctuation of physicochemical parameters of Hasadanga beel was aimed to be studied. A three-year study on the relationship between the seasonal fluctuation of water quality parameters and fish biodiversity indices was conducted in Hasadanga Beel, a floodplain lake of Nadia district, West Bengal to measure the ecological health of the lake. Samples of water and fish species were collected at pre-monsoon, monsoon and post-monsoon period from 2015-2017 to estimate physicochemical parameters of water and fish biodiversity indices i.e. Shannon-Weaver species diversity index, Margalef’s Species richness index, Pielou’s Species evenness index and Simpson’s index of dominance. Total of 34 different fish species belonging to 8 Orders were found during the study period which varies seasonally. Water temperature (20.0-31.4 °C), pH (7.70-8.75), dissolved oxygen (3.9-5.0 mg/l), Free CO2 (0.0-15.0 mg/l), total alkalinity (156-193 mg/l), hardness (113-145 mg/l), and BOD (1.03-1.94 mg/l) values varied significantly (p<0.05) between three seasons. Shannon-Weaver species diversity index (Hꞌ) is ranged between 1.2911-1.3502, Margalef’s species richness index (D) is measured between 12.72-14.15, Pielou’s species evenness index (Jꞌ) is recorded between 0.8829-0.9140 and Simpson’s index of dominance (ID) is ranged between 0.05346-0.07139. Hꞌ has positive correlation with pH, alkalinity and hardness whereas negative correlation with temperature, free CO2, DO and BOD. D has positive correlation with pH, free CO2, DO and hardness whereas negative correlation with temperature, alkalinity and BOD. Jꞌ has positive correlation with temperature, pH, alkalinity and hardness and whereas negative correlation with free CO2, DO and BOD. ID has positive correlation with temperature, free CO2, DO and BOD whereas negative correlation with pH, alkalinity and hardness. The obtained result suggests that various water quality parameters specially temperature, dissolved oxygen and pH are the key factors to regulate the fish biodiversity indices and should be taken into consideration for making policies for sustainable use of floodplain lakes.
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Joshi*, Nitesh, Prachiti Mule, and Ambika Joshi. "Study of roadside weed diversity along the constructed and non constructed roads in Palghar, Maharashtra, India." Annals of Plant Sciences 5, no. 06 (July 20, 2016): 1363. http://dx.doi.org/10.21746/aps.2016.06.004.
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The study aims to explore the floristic diversity of the weeds occurring along the roadside of the Palghar Tehsil by calculating various diversity indices of two distinctly identified sites, one being disturbed, constructed sites with high usage while other is relatively less disturbed mainly non-constructed sites and limited usage. The further purpose of the study was to draw conclusion in terms of floristic differences based on 3 indices viz. Shannon Weiner Index, Species Richness, Species evenness Index, Simpson’s Index and Sorenson’s Similarity Index. On comparison it was seen that the area that has limited usage has evenly distributed community and rich diversity as compared to another site. Diversity of the community occurring near non constructed road was found to be more as compared to the community occurring near constructed road.
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YULIANA, ERNIK, YUNI TRI HEWINDATI, ADI WINATA, WIBOWO A. DJATMIKO, and ATI RAHADIATI. "Diversity and characteristics of mangrove vegetation in Pulau Rimau Protection Forest, Banyuasin District, South Sumatra, Indonesia." Biodiversitas Journal of Biological Diversity 20, no. 4 (April 1, 2019): 1215–21. http://dx.doi.org/10.13057/biodiv/d200438.
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Abstract. Yuliana E, Hewindati YT, Winata A, Djatmiko WA, Rahadiati A. 2019. Diversity and characteristics of mangrove vegetation in Pulau Rimau Protection Forest, Banyuasin District, South Sumatra, Indonesia. Biodiversitas 20: 1215-1221. The purpose of the study was to analyze the flora diversity and characteristics of mangrove vegetation in Pulau Rimau Protection Forest, Banyuasin District, South Sumatra. Data collected were the number and girth diameter of mangrove tree species, and aquatic ecology parameters using transect method. The sample plots size were 2m×2 m; 5m×5 m; 10m×10 m; for seedling, sapling, and tree, respectively. The observation plots were arranged in a row of 120 m length on two sides of the forest edge, namely Calik Riverbank and Banyuasin Riverbank. Data were analyzed using importance value index (IVI), Simpson’s diversity index and Sørensen’s community similarity. The study revealed that there were differences in mangrove characteristics in two study sites. There were 57 plant species identified inside and outside sample plots, but only 15 species (26.32%) among them were categorized as true mangrove species. Inside the sample plots, there were 11 and 10 mangrove tree species recorded on the Calik Riverbank and Banyuasin Riverbank, respectively, but only 7 species among them were found in both sites. The mangroves on Calik Riverbank were dominated by Nypa (IVI 53.59%) and Bruguiera (51.12%), while those on Banyuasin Riverbank were dominated by Sonneratia (66.91%) and Avicennia (51.73%). The Simpson’s diversity index for Calik Riverbank and Banyuasin Riverbank was 0.82 and 0.78, respectively, whereas the Sørensen’s coefficient of community between the two sites was 0.67.
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Maurice Bilung, Lesley, Lai Sin Chai, Ahmad Syatir Tahar, Chong Kian Ted, and Kasing Apun. "Prevalence, Genetic Heterogeneity, and Antibiotic Resistance Profile ofListeriaspp. andListeria monocytogenesat Farm Level: A Highlight of ERIC- and BOX-PCR to Reveal Genetic Diversity." BioMed Research International 2018 (July 3, 2018): 1–12. http://dx.doi.org/10.1155/2018/3067494.
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This study aimed to identifyListeriaspp. andL. monocytogenes, characterize the isolates, and determine the antibiotic resistance profiles of the isolatesListeriaspp. andL. monocytogenesin fresh produce, fertilizer, and environmental samples from vegetable farms (organic and conventional farms). A total of 386 samples (vegetables, soil, water, and fertilizer with manure) were examined. The identification of bacterial isolates was performed using PCR and characterized using ERIC-PCR and BOX-PCR. The discriminating power of the typing method was analyzed using Simpson’s Index of Diversity. Thirty-four (n=34)Listeriaisolates were subjected to antimicrobial susceptibility test using the disc-diffusion technique. The PCR analysis revealed thatListeriaspp. were present in 7.51% (29/386) of all the samples (vegetable, soil, fertilizer, and water). None of the samples examined were positive for the presence ofL. monocytogenes.Percentages of 100% (15/15) and 73.30% (11/15) of theListeriaspp. isolated from vegetables, fertilizer, and soil from organic farm B had indistinguishable DNA fingerprints by using ERIC-PCR and BOX-PCR, respectively.Listeriaspp. isolated from 86 samples of vegetable, fertilizer, and environment of organic farm A and conventional farm C had distinct DNA fingerprints. Simpson’s Index of Diversity, D, of ERIC-PCR and BOX-PCR is 0.604 and 0.888, respectively. Antibiotic susceptibility test revealed that most of theListeriaspp. in this study were found to be resistant to ampicillin, rifampin, penicillin G, tetracycline, clindamycin, cephalothin, and ceftriaxone. The isolates had MAR index ranging between 0.31 and 0.85. In conclusion, hygienic measures at farm level are crucial to the reduction ofListeriatransmission along the food chain.
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de Abreu, Raimunda Liege Souza, Greicilany de Araújo Ribeiro, Bazilio Frasco Vianez, and Ceci Sales-Campos. "Insects of the Subfamily Scolytinae (Insecta: Coleoptera, Curculionidae) Collected with Pitfall and Ethanol Traps in Primary Forests of Central Amazonia." Psyche: A Journal of Entomology 2012 (2012): 1–8. http://dx.doi.org/10.1155/2012/480520.
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An experiment was conducted in a primary forest area of the Tropical Forest Experimental Station, 45 km from Manaus-Boa Vista Highway, in order to compare the insect fauna of the subfamily Scolytinae, in flight activity and on the ground. Five impact traps of the type Escolitideo/Curitiba, with ethanol baits, were installed at the height of 3 m above the ground, and five pitfall traps were buried in the same area of the above ground traps. The data collections were evaluated through abundance, richness, and Simpson diversity index, and, to compare these data with the pitfalls and the months collection, the ANOVA was used. The Pearson correlation test was also carried out to evaluate the meteorological factors (temperature and rainfall). From the total of 2,910 Scolytinae, 2,341 were captured in pitfall traps representing 80.45% and 569 with Escolitideo/Curitiba traps representing 19.55%. The most abundant species in the collections wereXyleborus volvulusFabricius andXyleborus affinisEichhoff, and this was classified as constant in both habitats. The result of the analysis indicates that the Simpson’s index was high and that the abundance of insects was affected by the types of trap and by the month of collection. The analysis of correlation with meteorological factors showed that onlyXyleborus spinulosusspecies presented significant correlation with temperature.
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Gautam, Tilak Prasad, and Tej Narayan Mandal. "Effect of disturbance on plant species diversity in moist tropical forest of eastern Nepal." Our Nature 16, no. 1 (December 31, 2018): 1–7. http://dx.doi.org/10.3126/on.v16i1.21558.
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Species diversity is a key factor for the stability of ecosystems but the increasing disturbances in tropical forests resulted in the shrinkage of biological diversity. This study was conducted in undisturbed and disturbed stands of Sal (Shorea robusta Gaertn.) dominated moist tropical forest of Sunsari district, eastern Nepal in order to understand the herb, shrub and tree diversity. Present study reported the 47, 16 and 60 species of herbs, shrubs and trees, respectively. The species richness and the Shannon–Wiener index for tree species were higher in undisturbed forest (9.11 and 3.08, respectively), while the Simpson’s index (index of dominance) was higher in disturbed forest (0.11). On the other hand, reverse case was found for shrubs and herbs where species richness and Shannon–Wiener index were higher but index of dominance was lower in disturbed forest. Changes in species diversity pattern reflect the effect of disturbance.
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Bagchi, Biplab. "Diversity and antimicrobial activity of endophytic fungi from Combretum sp. collected in monsoon from three regions." International Academic Publishing House 24 (April 30, 2021): 1–9. http://dx.doi.org/10.52756/ijerr.2021.v24.001.
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Aerial tissues of the woody lianas- Combretum sp. was selected and assessed for study of endophytic fungal diversity from three forest areas of West Medinipur and Jhargram districts of West Bengal. In monsoon study it was observed that out of 225 various tissue segments ,165 segments had been colonized by endophytic fungi Combretum roxburghii and 209 endophytic isolates were isolated from them. Average colonization frequency (CF)was 73.32 percent. Highest CF was in plant of Belpahari (76%) and in petiole (82.66%). Out of isolated fungal genera Pestalotiopsis sp. was highest in number. Diplodia sp., Beltrania sp., Chaetomium sp., Fusarium sp., Arthrinium sp. were also greater in number. Dominance index was highest in Belpahari (0.1547). Simpson’s diversity was maximum in Godapiasal (0.8693) and Shannon-Wiener index was also highest (2.152) in plant of Godapiasal. Highest diversity of endophytic fungi was in plants of Chilkigarh. Isolated endophytic fungi were Lasiodiplodia sp., Diplodia sp., Fusarium sp., Chaetomium sp., Arthrinium sp., Aspergillus sp., Pestalotiopsis sp. etc. Simpson’s diversity and Shannon-Wiener index were maximum in plants of Godapiasal. The study of antimicrobial activity of isolated fungal endophytes indicated that few plugs showed antimicrobial activity against few pathogenic bacteria. Among all isolates tested only seven showed antimicrobial activity. Aspergillus sp. and one unidentified fungi showed the antimicrobial activity against three bacteria i. e., Bacillus cereus, Escherechia coli and Vibrio cholera and maximum inhibition zone was observed against E. coli, diameter of inhibition zone is 1.4 cm. Other fungi showed less antimicrobial activity. Diameter of zone of inhibition varied (0.7 – 1.4) and this variation might be due to the difference of bioactive compound produced or the varied concentrations or amount degree of same compound.
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Victor, Awé Djongmo, Noiha Noumi Valery, and Zapfack Louis. "Floristic structure and ecological role of Rourea afzelii stand in three savannah ecosystems from Cameroon." Journal of Tropical Resources and Sustainable Science (JTRSS) 8, no. 1 (July 13, 2021): 5–11. http://dx.doi.org/10.47253/jtrss.v8i1.157.
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The present study investigated the floristic structure and ecological role of Rourea afzelii stands insavannah, forest galleries and swampy areas to Cameroon. An 80 m x 50 m transect method wasundertaken to measure floristic diversity using Shannon index, Pielou equitability, Simpson’s indexand the importance value index. The structure of Rourea afzelii stands is determined by density,basal area and biovolume. The results of this study show that Rourea afzelii stands are morediversified in savannah with a Shannon diversity index (ISH =4 ± 0.03bit). The highest log stabilityof Rourea afzelii stands is observed in the savannah (EQ=0.75 ± 0.008). The Simpson index of theRourea afzelii stands is larger in the forest gallery (D=0.088 ± 0.0022). Rourea afzelii Stands aredenser in savannah (113 ± 2.54 individuals/ha). The basal area and biovolume of Rourea afzeliistands are very high in swamp area (St=15.75 ± 0.02 m2/ha, Biov=9.08 ± 0.12 m3/ha). The diametricstructure has an asymmetrical “L” shaped appearance, indicating a strong regeneration of Roureaafzelii Stands in the three sites studied. Rourea afzelii Stands in forest galleries sequestered morecarbon (26.41 ± 0.0015 ton C/ha) than those in savannahs and swampy areas. This valuecorresponds to sequestration of carbon dioxide of 96.92 ± 0.82 ton CO2/ha. Economically, thiscorresponds to the CDM carbon price (290.77± 3.332 Euros/ha), a Voluntary Market Carbon Priceof 455.54 ± 1.908 Euros/ha, a REDD + carbon price of 9692 ± 8.152 Euros/ha. In conclusion, theresults of this study can be used in the context of protection and conservation as well as thedomestication of such a species.
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Louadi, K., and S. Doumandji. "DIVERSITÉ ET ACTIVITÉ DE BUTINAGE DES ABEILLES (HYMENOPTERA APOIDEA) DANS UNE PELOUSE À THÉROPHYTES DE CONSTANTINE (ALGÉRIE)." Canadian Entomologist 130, no. 5 (October 1998): 691–702. http://dx.doi.org/10.4039/ent130691-5.
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AbstractThe study of bee diversity and activity was conducted from January until June 1994 in a natural vegetation parcel (6200 m2) in Constantine (Algeria). The results showed the presence of 10 genera of wild bees visiting natural flowers and belonging to four families: Andrenidae, Anthophoridae, Halictidae, and Megachilidae. The Apidae family was represented by honeybee (Apis mellifera L.) and bumblebee (Bombus ruderatus siculus Dalla Torre et Friese). Census of bee populations revealed the abundance of wild bees with 66.26% of flowers visits, honeybee with 31.98%, B. ruderatus and Xylocopa violacea with 1.59 and 0.17% of total fauna, respectively. The beginning flight activity of these species started from a minimum threshold of temperature and humidity. The alimentary specialization was quantified by Simpson’s diversity index (Is) and by Shannon’s diversity index (Ish). Apis mellifera had the highest floral visits index (Is = 0.866) and the broadest alimentary niche index (Ish = 0.316).
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Orfinger, Alexander B., Quan T. Lai, and Ryan M. Chabot. "Effects of Nonnative Fishes on Commercial Seine Fisheries: Evidence from a Long-Term Data Set." Water 11, no. 6 (June 4, 2019): 1165. http://dx.doi.org/10.3390/w11061165.
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Dozens of introduced exotic freshwater fish species inhabit the state of Florida. These nonnative fishes interact with freshwater commercial fisheries in a variety of ways, influencing catch abundance, composition, and revenue. Using a 22-year data set collected from a commercial haul seine fishery, we aimed to explore the dynamics of yield and revenue in relation to nonnative fishes, with emphasis on the suckermouth armored catfishes (Pterygoplichthys spp.). Using profit index metrics and the inverse Simpson’s diversity index, we found that non-native tilapia (Oreochromis spp.) and brown hoplo (Hoplosternum littorale) provided economic benefits while suckermouth armored catfishes seemed to disrupt catch consistency and lower profit index values. To reduce the negative impacts of the suckermouth armored catfishes and subsequently exert pressure on their population, we suggest marketing these edible fishes for human and/or animal consumption.
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Shrestha, Sabitri, Tilak Prasad Gautam, Tej Narayan Mandal, and Hari Prasad Aryal. "Ecology and Diversity of Ectomycorrhiza in moist Tropical Forest of Sunsari District, Eastern Nepal." Journal of Institute of Science and Technology 26, no. 1 (June 17, 2021): 35–42. http://dx.doi.org/10.3126/jist.v26i1.37815.
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An ectomycorrhiza plays a vital role in the maintenance and strengthening the forest ecosystems and diversity. This study attempts to assess the ecology and diversity of ectomycorrhiza in tropical Sal (Shorea robusta Gaertn.) forest in Sunsari district, eastern Nepal. The collection of ectomycorrhiza was carried out from June to September (rainy season) for the year 2019-2020. A total of 18 species of ectomycorrhiza belonging to 12 genera and 7 families were collected. Russulaceae was found to be the dominant family representing 7 species. As per the diversity indices, the Shannon Weiner index and Simpson’s index were found to be 2.60 and 0.913, respectively indicating a higher value for the index of diversity. The results conclude that the moist tropical forest of Sunsari district is rich in ectomycorrhizal fungi, which consequently may provide a great opportunity for nutrient absorption
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Monroy-Velázquez, Luz Verónica, Rosa E. Rodríguez-Martínez, Paul Blanchon, and Fernando Alvarez. "The use of artificial substrate units to improve inventories of cryptic crustacean species on Caribbean coral reefs." PeerJ 8 (November 23, 2020): e10389. http://dx.doi.org/10.7717/peerj.10389.
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Motile cryptofauna inhabiting coral reefs are complex assemblages that utilize the space available among dead coral stands and the surrounding coral rubble substrate. They comprise a group of organisms largely overlooked in biodiversity estimates because they are hard to collect and identify, and their collection causes disturbance that is unsustainable in light of widespread reef degradation. Artificial substrate units (ASUs) provide a better sampling alternative and have the potential to enhance biodiversity estimates. The present study examines the effectiveness of ASUs made with defaunated coral rubble to estimate the diversity of motile cryptic crustaceans in the back-reef zone of the Puerto Morelos Reef National Park, Mexico. Species richness, Simpson’s diversity index, Shannon–Wiener index and the composition of assemblages were compared between ASUs and samples from the surrounding coral rubble substrate. A combined total of 2,740 specimens of 178 different species, belonging to five orders of Crustacea (Amphipoda, Cumacea, Isopoda, Tanaidacea and Decapoda) were collected. Species richness was higher in the surrounding coral rubble and Shannon–Wiener and Simpson indexes were higher in ASUs. Species composition differed between methods, with only 71 species being shared among sampling methods. Decapoda was more speciose in ASUs and Peracarids in the surrounding coral rubble. Combining the use of ASUs with surrounding rubble provided a better inventory of motile cryptic crustacean biodiversity, as 65% of the species were represented by one or two specimens.
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Ali, Mir Mohammad, Md Lokman Ali, Md Jalilur Rahman, and Md Abdul Wahab. "Fish Diversity in the Andharmanik River Sanctuary in Bangladesh." Croatian Journal of Fisheries 78, no. 1 (March 1, 2020): 21–32. http://dx.doi.org/10.2478/cjf-2020-0003.
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AbstractLoss of fish biodiversity, especially in the inland and coastal areas, is a major concern in sustainable fish production. Indiscriminate fish catch, climate change and many other anthropogenic activities synergistically affect fish biodiversity. To formulate a sustainable fish biodiversity conservation plan, fish biodiversity in the Andharmanik River, a 40-km-long Hilsa shad sanctuary in the southern part of Bangladesh, was assessed. The study was conducted to understand the status of fish species diversity through sampling in three sampling stations between December 2014 and November 2015. A total of 93 fish species were found belonging to 66 genera, 45 families and 14 orders. Perciformes (27.65%) was found to be the most dominant order, followed by Cypriniformes (20.21%), Siluriformes (21.28%) Clupeiformes (7.45%) Mastacembeliformes (4.26%) and Channiformes (4.26%). Out of the 93 fish species of the river, the percentage compositions of the vulnerable, endangered, critically endangered and not threatened were found to be 14%, 11%, 6% and 59%, respectively. Four population indices viz. Shannon-Wiener’s diversity index (H), Simpson’s dominance index (D), Simpson’s index of diversity (1-D) and Margalef’s index (d) were applied to demonstrate species diversity, richness and evenness of fish species in sampling areas, and the overall values of the indices were 2.70-3.51, 0.10-0.12, 0.88-0.90 and 7.84-8.19, respectively. The main threats to fish biodiversity were reviewed and the measures for fish biodiversity conservation of the river recommended. Indiscriminate fishing using biodiversity destructive gears, as well as losing hydrological and ecological connectivity with the surrounding habitats, were identified as major threats to biodiversity in the Andharmanik River. Effective sanctuary-based co-management, immediate actions for habitat enhancement to conserve and improve fish biodiversity in the river were recommended. Necessary steps to improve hydrological and ecological connectivity for habitat protection and elimination of all destructive fishing gears in order to conserve biodiversity in the Andharmanik River were also suggested.
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Supriatna, Jatna. "Biodiversity Indexes: Value and Evaluation Purposes." E3S Web of Conferences 48 (2018): 01001. http://dx.doi.org/10.1051/e3sconf/20184801001.
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Biodiversity is a word recently introduced by experts in the field of biology. This word became more meaningful after Edward O. Wilson of Harvard University introduced it in a book entitled Biodiversity, an extension of biological diversity, in 1989 [11]. In subsequent developments, it became very popular and used not only by environmental biologists but also by researchers, environmentalists, funders, educators, social experts, economists, policy makers, and many others, although many do not know what that means. Biodiversity includes variations within the biological community, where living species, and ecosystems, where communities are located, as well as interaction between them (Pri. The science of biodiversity has emerged rapidly since then included monitoring and evaluation systems which is measuring the value of biodiversity components, such as the number of species present, the population of species, a habitat or the sum of all such components within a given area or site. Such monitoring and evaluation may be carried out for a variety of reasons, included identification of a given area for biodiversity richness, evenness or healthy ecosystems. The richness is the number of species per sample, the more species present in a sample, the richer the sample. Evenness is a measure of the relative abundance of the different species making up the richness of an area. Two commonly used to measure biodiversity Simpson index Ds and Shannon’s index H’. Simpson’s index DS is similarity index (the higher the value the lower in diversity). While Shannon index is combining evenness and richness and less weighted on dominant species. Both indexes are more reflective in nature and can predict the environment health. Therefore, it may be good to have one of those biodiversity indexes to be used for UI GreenMetric to understand the environment healthiness in the campus.
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Thambiratnam, Sivaruban, Barathy Sivaruban, Srinivasan Pandiarajan, and Isack Rajasekaran. "Temporal variation of mayfly community (Ephemeroptera) in response to ecological attributes in Gadana river, Tamilnadu, India." ENTOMON 45, no. 2 (June 30, 2020): 115–22. http://dx.doi.org/10.33307/entomon.v45i2.519.
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In the study of diversity and distribution of Ephemeroptera in Gadana River and relationship between Ephemeropteran community and ecological factors, revealed a total of 2056 specimens belonging to 25 genera and 7 families. The diversity and distribution of Ephemeroptera were higher during the rainy season, contrasted with non-rainy period. The high scores of Shannon index and Simpson’s index indicate that Gadana River is hale and healthy and it bolsters more diverse taxa. The pH values accomplish greatest range in the months of January and August; it legitimately impacts on diversity of mayflies. Leptophlebiidae and Baetidae were the most ubiquitous families present in the Gadana River. Canonical Correspondence Analysis (CCA) shows that rainfall, pH, DO and water temperature were to be the significant stressor in altering the community structure of mayflies.
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Sharma, Arti, and Meenu Sharma. "Zooplankton Diversity in Relation to Physico-Chemical Parameters in Subtropical Pond of Jammu, Jammu and Kashmir, India." Biosciences, Biotechnology Research Asia 16, no. 2 (June 27, 2019): 425–39. http://dx.doi.org/10.13005/bbra/2758.
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The study aim to investigate the zooplankton diversity in relation to physico-chemical parameters of surface water in Barnai pond of Jammu district. Water parameters were analysed by following various standard methods, where as zooplankton were collected through the plankton net of standard bolting silk cloth no. 25 (mesh size 0.003-0.004 μm) and the total number of zooplankton was counted by using Drop count method. Statistical analysis of data involves Pearson’s Correlation analysis and various diversity indices viz; Shannon-Wiener diversity index (H´), Simpson’s Index (D), Margalef’s Index (d´) and Pielou’s Evenness (J). A total of 38 zooplankton taxa along with Nauplius larvae were observed belonging to 5 major taxonomic groups: Protozoa (6 species), Rotifera (21species), Cladocera (6 species), Copepoda (3 species) and Ostracoda (2species). Physico-chemical parameters of Barnai pond revealed well marked fluctuations with maxima and minima values of each parameter during specific seasons and zooplankton analysis revealed seasonal variations with an increase during summer and a fall during winter and monsoon seasons.
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Daniel, J. Alfred, and K. Ramaraju. "Collecting parasitic Aculeata (Hymenoptera) from rice ecosystems of Tamil Nadu, India." Journal of Threatened Taxa 12, no. 8 (May 26, 2020): 15828–34. http://dx.doi.org/10.11609/jott.4724.12.8.15828-15834.
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Surveys were conducted to explore the parasitic aculeate fauna in rice ecosystems of Tamil Nadu in 2015–2016 in three different rice growing zones, viz., the western zone, the Cauvery delta zone and the high rainfall zone. The study recorded a total of 32 aculeates that represent 12 species under seven families belonging to three super families, viz., Apoidea (Apidae), Chrysidoidea (Bethylidae, Chrysididae, & Dryinidae), and Vespoidea (Mutillidae, Scoliidae, & Thiphiidae). Alpha and beta diversity were computed for the three zones and the diversity indices (Simpson’s index, Shannon-Wiener index, Pielou’s index) revealed the high rainfall zone as the most diverse zone, with the Cauvery delta zone being the least diverse. On comparing the species similarities using the Jaccard’s index in between the three zones taken in pairs, it was found that 42 per cent similarity existed between the western and Cauvery delta zone and 11 per cent similarity between high rainfall and Cauvery delta zones and 16 per cent similarity between the high rainfall and western zones.
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Blanco-Sacristán, Javier, Cinzia Panigada, Giulia Tagliabue, Rodolfo Gentili, Roberto Colombo, Mónica Ladrón de Guevara, Fernando T. Maestre, and Micol Rossini. "Spectral Diversity Successfully Estimates the α-Diversity of Biocrust-Forming Lichens." Remote Sensing 11, no. 24 (December 9, 2019): 2942. http://dx.doi.org/10.3390/rs11242942.
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Biocrusts, topsoil communities formed by mosses, lichens, liverworts, algae, and cyanobacteria, are a key biotic component of dryland ecosystems worldwide. Experiments carried out with lichen- and moss-dominated biocrusts indicate that climate change may dramatically reduce their cover and diversity. Therefore, the development of reproducible methods to monitor changes in biocrust diversity and abundance across multiple spatio-temporal scales is key for evaluating how climate change may impact biocrust communities and the myriad of ecosystem functions and services that rely on them. In this study, we collected lichen-dominated biocrust samples from a semi-arid ecosystem in central Spain. Their α-diversity was then evaluated using very high spatial resolution hyperspectral images (pixel size of 0.091 mm) measured in laboratory under controlled conditions. Support vector machines were used to map the biocrust composition. Traditional α-diversity metrics (i.e., species richness, Shannon’s, Simpson’s, and Pielou’s indices) were calculated using lichen fractional cover data derived from their classifications in the hyperspectral imagery. Spectral diversity was calculated at different wavelength ranges as the coefficient of variation of different regions of the reflectance spectra of lichens and as the standard deviation of the continuum removal algorithm (SD_CR). The accuracy of the classifications of the images obtained was close to 100%. The results showed the best coefficient of determination (r2 = 0.47) between SD_CR calculated at 680 nm and the α-diversity calculated as the Simpson’s index, which includes species richness and their evenness. These findings indicate that this spectral diversity index could be used to track spatio-temporal changes in lichen-dominated biocrust communities. Thus, they are the first step to monitor α-diversity of biocrust-forming lichens at the ecosystem and regional levels, a key task for any program aiming to evaluate changes in biodiversity and associated ecosystem services in drylands.
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Mohamad Radhi, Amonodin, Hashim Rohasliney, and Hazrin Zarul. "Fish Composition and Diversity in Perak, Galas and Kelantan Rivers (Malaysia) after the Major Flood of 2014." Transylvanian Review of Systematical and Ecological Research 19, no. 3 (July 1, 2017): 41–56. http://dx.doi.org/10.1515/trser-2017-0020.
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Abstract Fish from three major rivers, namely the Kelantan River (KR) and the Galas River (GR) in Kelantan, and the Perak River (PR) in Perak, Malaysia, were caught using gill nets with different mesh sizes, cast nets, and the electroshock method. There were 14 fishes representing five families and five fish species were collected from the Kelantan systems in February 2015. While the Galas system holds more fish, 48 individual fishes comprising of four families and 10 fish species were found there. A total of 213 fish specimens representing 10 families and 22 species were captured in PR in May 2015. For diversity index, PR had the highest value due to the catchment area and the environmental condition: Shannon-Weiner index (H’) (2.54), Species Evenness (J’) (0.73) and Simpson’s Dominance (D’) (8.93), compared to GR (H’) (2.09) (J’) (0.603) (D’) (6.52) and KR (H’) (1.62) (J’) (0.47) (D’) (5.62).
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Daniel, J. Alfred, K. Ramaraju, and A. Rameshkumar. "Comparative studies of mymarid diversity from three different zones of paddy ecosystem in Tamil Nadu, India." ENTOMON 44, no. 3 (October 31, 2019): 173–82. http://dx.doi.org/10.33307/entomon.v44i3.458.
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Surveys were conducted to explore the mymarid fauna from three different rice growing zones viz., western zone, Cauvery delta zone and high rainfall zone in Tamil Nadu during 2015-16. In the present study, 92 mymarid parasitoids comprising of 8 species under 7 genera viz., Anagrus sp., Anaphes sp., Camptoptera sp., Dicopus longipes (Subba Rao), Lymaenon delhiensis Narayanan and Subba Rao, Lymaenon munnarus Mani and Saraswat, Mymar pulchellum Curtis and Ptilomymar dictyon Hayat and Anis were collected. Alpha and beta diversity were computed for the three zones and the diversity indices (Simpson’s index, Shannon-Wiener index, Pielou’s index) revealed high rainfall zone as the most diverse zone, while Cauvery delta zone being the least diverse. Dicopus longipes is found to the predominant species in rice ecosystem. Jaccard’s index of species similarity comparison revealed 42.5 per cent similarity between western and Cauvery delta zones and 62.5 per cent similarity between high rainfall and Cauvery delta zones and 62.5 per cent similarity between high rainfall and western zones. Correspondence analysis and Bray-curtis cluster analysis were also done to understand the diversity assemblage of the mymarids that were collected.
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Begum, Syeda Salma. "Hydrophytes In The High Barind Tract: Diversity Status Threats And Conservation." Journal of the Asiatic Society of Bangladesh, Science 40, no. 2 (December 30, 2014): 259–70. http://dx.doi.org/10.3329/jasbs.v40i2.46024.
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A survey was conducted to assess the diversity of hydrophytes in some selected locations including Kharoil Beel (Mohanpur), Beel Kumari (Tanore) and Jobai Beel (Sapahar) situated in High Barind Tract, Rajshahi, Bangladesh from June 2005 to May 2008. Among them Jobai Beel is the largest, Beel Kumari is medium and Kharoil Beel is small in size. At experimental areas a total of 151 plant species and 90 genera distributed in 44 families was identified. From the result, diversity status of the study areas, the values ranged between 0.94-0.97 in Simpson’s index and 3.55-4.13 in Shannon’s index. Diversity status of three study areas shows richness. Sequence of richness is as follows- Kharoil Beet> Beel Kumari > Jobai Beel. It is also evident that these wetlands are disturbed by anthropogenic activities. Some of the species have become threatened, some have become rare. Conservation efforts and awareness building are perquisite for the sustainability of these wetlands
Asiat. Soc. Bangladesh, Sci. 40(2): 259-270, December 2014
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Pen-Mouratov, S., C. Hu, E. Hindin, and Y. Steinberger. "Effect of sand-dune slope orientation on soil free-living nematode abundance and diversity." Helminthologia 47, no. 3 (September 1, 2010): 179–88. http://dx.doi.org/10.2478/s11687-010-0027-6.
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AbstractThe spatial and temporal dynamics and composition of a soil free-living nematode community were studied in order to determine the impact of slope orientation on the community on the xeric south- and the mesic north-facing sand-dune slopes.A significant effect of sampling location on organic matter, total number of free-living nematodes, and trophic diversity was found. Although soil moisture had a significant effect on separate nematode trophic groups and on most of the applied ecological indices, no differences in soil moisture were observed between slopes. Organic matter was found to have a significant effect on the fungivore nematodes. The obtained results indicate that the south-facing slope is more favorable for the observed free-living nematodes than the other sampling sites. Twenty-four of the 77 nematode species that were found in the observed area showed dependence on dune slope orientation. The fungibacteria ratio, Simpson’s dominance index, and basal index were useful tools for determining slope differences.
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Hu, Weiyan, Siyu Zhang, Yan Song, Tian Liu, Yingchao Lin, and Anlu Zhang. "Effects of Multifunctional Rural Land Use on Residents’ Wellbeing: Evidence from the Xinzhou District of Wuhan City, China." Sustainability 10, no. 10 (October 19, 2018): 3787. http://dx.doi.org/10.3390/su10103787.
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The purpose of this article is to analyze the effects of multifunctional rural land use (MRLU) on residents’ wellbeing. A questionnaire survey on 805 rural residents in 64 villages of the Xinzhou District of Wuhan city in China, and estimators of OLS, ordered logit, and ordered probit were employed. The Shannon’s H index and Simpson’s Reciprocal Index are used to measure MRLU and the life satisfaction approach is used to measure wellbeing. An inverted-U pattern is observed in the relationship between MRLU and wellbeing, and another finding of the study is the threshold of MRLU. The article contributes to the literature by integrating MRLU into wellbeing analysis from a spatial-separated form, and deepens the relationship between MRLU and the residents’ wellbeing. MRLU is characterized by differences and a moderation, which can provide a reference for profiling rural land use planning and for designing land-use policy, and for prompting rural sustainable development.
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Gonino, Gabriel, Evanilde Benedito, Vivian de Mello Cionek, Maria Teresa Ferreira, and João Manuel Oliveira. "A Fish-Based Index of Biotic Integrity for Neotropical Rainforest Sandy Soil Streams—Southern Brazil." Water 12, no. 4 (April 24, 2020): 1215. http://dx.doi.org/10.3390/w12041215.
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Multimetric indices are considered a low-cost and rapid means of assessing ecological integrity in streams. This study aimed to develop a fish-based Index of Biotic Integrity (N3S-IBI) in an agricultural region within the domains of the Atlantic rainforest in Brazil. We sampled 23 first-order streams and used large-scale land use and a local physical condition index to choose reference sites and to classify sites according to the disturbance level. N3S-IBI resulted in six metrics (Simpson’s dominance; the numbers of Characiformes and non-native individuals (Poecilia reticulata); and the percentages of Characidae species, intolerant insectivorous individuals, and tolerant species), contemplating tolerance, composition, abundance, richness, trophic habits, and origin. The low number of metrics contributes to a quick and easy biomonitoring process. N3S-IBI showed an excellent performance to separate least and most disturbed sites in our study area and can provide additional knowledge about anthropogenic effects within this impacted region. In fact, this tool could be utilized by managers to direct restoration actions for the most disturbed sites and to strengthen the preservation of the least disturbed sites.
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Kwon, Young-Doo, Soon-Bum Kwon, Bo-Kyung Shim, and Hyun-Wook Kwon. "Comprehensive Interpretation of a Three-Point Gauss Quadrature with Variable Sampling Points and Its Application to Integration for Discrete Data." Journal of Applied Mathematics 2013 (2013): 1–8. http://dx.doi.org/10.1155/2013/471731.
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This study examined the characteristics of a variable three-point Gauss quadrature using a variable set of weighting factors and corresponding optimal sampling points. The major findings were as follows. The one-point, two-point, and three-point Gauss quadratures that adopt the Legendre sampling points and the well-known Simpson’s 1/3 rule were found to be special cases of the variable three-point Gauss quadrature. In addition, the three-point Gauss quadrature may have out-of-domain sampling points beyond the domain end points. By applying the quadratically extrapolated integrals and nonlinearity index, the accuracy of the integration could be increased significantly for evenly acquired data, which is popular with modern sophisticated digital data acquisition systems, without using higher-order extrapolation polynomials.
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Piekarska-Boniecka, Hanna, Justyna Ratajczak, and Ewa Dolańska-Niedbała. "Parasitic wasps of the Pimplinae, Poemeniinae and Diacritinae (Hymenoptera, Ichneumonidae) subfamilies at Kórnik Arboretum." Folia Horticulturae 21, no. 1 (June 1, 2009): 119–27. http://dx.doi.org/10.2478/fhort-2013-0131.
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Abstract The research was carried out in 2005 − 2007 in the area of the Kórnik Arboretum and covered parasitoids of the Pimplinae, Poemeniinae and Diacritinae (Hymenoptera, Ichneumonidae) subfamilies, which control a number of plantdamaging phytophages. The quality and quantity composition of the parasitoids was defined, and the characterization of Pimplinae communities was carried out on the basis of the following biocenotic indices: Shannon’s diversity index H’, Pielou’s evenness index J’ and Simpson’s diversity index d. The Pimplinae communities were compared in terms of quality using the method of the Marczewski-Steinhaus MS index. Thirty-one species of Pimplinae were found; they account for 23.3% of the national fauna and 43.0% of species reported for Wielkopolska. Three species of Poemeniinae and one species of Diacritinae were also found. Among Pimplinae the prevailing species were those which decrease the number of pests belonging to exo- and endophytophages of Micro- and Macrolepidoptera. The dominants were: Pimpla contemplator (Muelle.) − 24.9%, Pimpla flavicoxis Thoms. − 12.3%, Pimpla insignatoria (Grav.) − 9.1%, Itoplectis maculator (F.) − 6.3% and I. alternans (Grav.) − 5.9%. Poemeniinae included Poemenia brachyura Holmgr. and P. herctica (Grav.), belonging to parasitoids of xylophages. Diacritinae were represented by Diacritus aciculatus (Voll.), whose trophic links are not yet known.
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Nadeau, Martin B., and Thomas P. Sullivan. "Relationships between Plant Biodiversity and Soil Fertility in a Mature Tropical Forest, Costa Rica." International Journal of Forestry Research 2015 (2015): 1–13. http://dx.doi.org/10.1155/2015/732946.
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We aimed to study relationships between plant biodiversity and soil chemical fertility in a mature tropical forest of Costa Rica. Soil samples were collected in nine sampling plots (5 m by 25 m) in order to identify P, K, Ca, Mg, Fe, Zn, Mn, Cu, and Al and total N contents, soil fertility index, CEC, pH, and C/N ratio. Furthermore, species richness, Shannon-Wiener and Simpson’s species diversities, structural richness, and structural diversity were calculated for each plot. Simple linear regression analyses were conducted. Tree species richness was inversely related to concentration levels of K, Ca, and P, CEC, and soil fertility index. Therefore, higher tree species richness tended to be found on sites with lower soil fertility, which is the complete opposite of temperate forests. As a result, tropical and temperate forest ecology should be considered separately. Shannon-Wiener tree species diversity was positively correlated to C/N ratio. Herb structural richness was positively correlated with soil fertility index and P concentration. Therefore, herb structural richness may be a good indicator of soil fertility. This study gives important insights on ecological relationships between plant biodiversity and soil chemical fertility in a primary tropical forest.
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Ramadan, Hazem, Charlene R. Jackson, Jonathan G. Frye, Lari M. Hiott, Mohamed Samir, Amal Awad, and Tiffanie A. Woodley. "Antimicrobial Resistance, Genetic Diversity and Multilocus Sequence Typing of Escherichia coli from Humans, Retail Chicken and Ground Beef in Egypt." Pathogens 9, no. 5 (May 8, 2020): 357. http://dx.doi.org/10.3390/pathogens9050357.
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Contamination of retail foods with foodborne pathogens, particularly the antimicrobial resistant ones, poses a persistent threat to human health. There is a dearth of information about the overlapping Escherichia coli (E. coli) lineages circulating among retail foods and humans in Egypt. This study aimed to determine the clonal diversity of 120 E. coli isolates from diarrheic patients (n = 32), retail chicken carcasses (n = 61) and ground beef (n = 27) from Mansoura, Egypt using pulsed-field gel electrophoresis (PFGE) and multilocus sequence typing (MLST). Simpson’s index of diversity was calculated to compare the results of both typing methods. Antimicrobial resistance phenotypes, genotypes and phylogrouping of the isolates were also determined. Higher frequencies of antimicrobial resistance were found among chicken isolates compared to beef and human isolates; regardless of isolate source, the predominant antimicrobial resistances were found against ampicillin (87/120, 72.5%), tetracycline and sulfisoxazole (82/120, 68.3%, each), and streptomycin (79/120, 65.8%). None of the isolates displayed resistance to meropenem. The prevalent genes detected were tetA (64.2%), blaTEM (62.5%), sul1 (56.7%), floR (53.3%), sul2 (50%), strB (48.3%) and strA (47.5%) corresponding with resistance phenotypes. Alarmingly, blaCTX was detected in 63.9% (39/61) of chicken isolates. The majority of E. coli isolates from humans (90.6%), beef (81.5%) and chicken (70.5%) belonged to commensal phylogroups (A, B1, C). Using PFGE analysis, 16 out of 24 clusters (66.7%) contained isolates from different sources at a similarity level ≥75%. MLST results assigned E. coli isolates into 25, 19 and 13 sequence types (STs) from chicken, human and beef isolates, respectively. Six shared STs were identified including ST1011, ST156, ST48, ST224 (chicken and beef), ST10 (human and chicken) and ST226 (human and beef). Simpson’s index of diversity was higher for MLST (0.98) than PFGE (0.94). In conclusion, the existence of common genetic determinants among isolates from retail foods and humans in Egypt as well as the circulation of shared STs indicates a possible epidemiological link with potential zoonotic hazards.
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Amori, Giovanni, Luigi Boitani, Giuliano Milana, Luigi Maiorano, and Luca Luiselli. "Endemism and diversity in European montane mammals: macro-ecological patterns." Biological Journal of the Linnean Society 128, no. 1 (July 4, 2019): 225–37. http://dx.doi.org/10.1093/biolinnean/blz081.
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Abstract Mountains are important landforms with regard to both biodiversity and evolution of endemism. We analysed macro-ecological patterns of distribution and endemism of European montane (i.e. with at least 70% of their range inside mountain areas) mammals. The landscape of the study area was characterized by three environmental variables: land cover, land-use and elevation. For each species, we collected spatially explicit information on the extent of occurrence, level of endemicity, conservation status, habitat preferences, elevation range and all the available presence points. Montane species accounted for 25.5% of the total (N = 66), whereas lowland species (N = 193) accounted for 74.5% of the total European mammals. There was a significantly lower mean range in size of montane species compared to non-montane species. There was a negative correlation between the number of species and elevation, and a negative correlation between median elevation of the range of a given species and its extent of occurrence. The highest peak in the percentage of species present in each altitudinal band was observed at lower elevations in the lower altitude mountain chains. There was a significantly negative correlation between elevation and Simpson’s index of habitats, but species richness increased significantly with Simpson’s index of habitat diversity. A total of 122 species (40.7%) were European endemics, with the frequencies of endemic species not being different between montane areas and overall. A logistic regression model showed that, for a given species, being montane also enhanced the probability of being endemic to Europe. Montane species are especially concentrated in the Caucasus, along the Turkish coast of the Black Sea. The area of the various mountain chains did not influence either the number of montane species or the number of montane species that are strictly endemic to that mountain chain. A total of 45 endemic montane species were recorded for the study region, with only ten being of conservation concern according to IUCN criteria.
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Coelho, M. R., R. A. L. Muzzi, C. B. Abreu, T. Schulien, L. A. L. Muzzi, L. E. D. Oliveira, and M. Cherem. "Assessment of left atrial function in dogs with myxomatous mitral valve disease by biplane simpson’s method." Arquivo Brasileiro de Medicina Veterinária e Zootecnia 70, no. 5 (October 2018): 1349–54. http://dx.doi.org/10.1590/1678-4162-9489.
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ABSTRACT The relationship between the diameter of the left atrium (LA) and aorta (Ao) is considered as a prognostic factor in chronic mitral valve disease. As the left atrium is a three-dimensional structure, methods based on measurement of the chamber volume can be more accurate than linear methods.The aim of this study was to assess the feasibility of measuring LA volume with 2D echocardiography using the biplane modified Simpson (SIMP) method in 33 dogs with various classes of myxomatous mitral valve disease (MMVD), as well as to present values of LA function using the atrial diastolic and systolic volume indices (ADVI and ASVI), cardiac index (ACI) and atrial ejection fraction (AEF). We observed agreement among the LA/Ao ratio and the atrial volume indices (ADVI and ASVI) and the ACI, suggesting that the values of the variables increase as the LA/Ao ratio increases due to atrial remodeling that accompanies MMVD progression. The data demonstrated a good assessment of atrial function, allowing a better understanding of LA's role in the pathophysiology of MMVD.
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Rzymowska, Zofia, Maria Ługowska, and Janina Skrzyczyńska. "Species diversity of segetal communities in tuber crops and in winter and spring cereals." Acta Agrobotanica 66, no. 3 (2013): 95–102. http://dx.doi.org/10.5586/aa.2013.043.
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The work presents the results of studies on the diversity of weed communities in tuber crops as well as in winter and spring cereals under similar climatic and soil conditions. We examined overall species abundance in the groups analysed, the average species number per relevé, as well as weed cover of the study area. Additionally, species composition, number of individual species and their biomass were determined. Dominant species in each crop group were distinguished. Species diversity was determined based on the following ecological indices: the Shannon-Wiener index of biodiversity <em>H’</em> and Simpson’s index of dominance <em>C</em>. The indices were computed on the biomass and number-of-species basis. The objective of the work was to compare the structure and diversity of weed communities in the crops studied. The communities analysed differed in all the characteristics examined. Differences were found between biodiversity and dominance indices calculated for individual crop groups, but their significance depended on the method applied to calculate the indices.
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Gupta, Manish Kumar, and Dr Anupama Jain. "Diversity and Distribution of Lepidopteran Butterflies in Kota District, Rajasthan." International Journal of Multidisciplinary Research Configuration 1, no. 2 (April 28, 2021): 24–29. http://dx.doi.org/10.52984/ijomrc1206.
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Understanding the standing point of biodiversity is an integral part of studying habitat ecology in the arena of the applied ecology and conservation biology. Considering this, a study was conducted to understand the biodiversity of the single species, i.e. Lepidoptera in four different sites of Kota district. Four distinct habitat fragmentation sites, Chambal Garden, Ganesh Udhyan, Industrial Area and agriculture land were selected to understand the diversity and distribution of lepidopteran butterfly. As this group of butterfly is considered as “umbrella taxa”, detailed study of its assemblages could be directly correlated with the changes in microclimates in the selected regions. Therefore, diversity of the Lepidoptera was calculated by Simpson’s index of diversity and Shannon-Weiner Index. Among these four areas, Chambal Garden and Ganesh Udhyan are dominated with the Lepidoptera whereas, decline in abundance could be observed remaining two areas. This study indicated a rich and diverse butterfly habitat in the selected survey area, which could be served a s a future referral for measuring and monitoring biological diversity.
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Jannat, M., M. Kamruzzaman, MA Hossain, and MK Hossain. "Tree species diversity in the forest of Renikhayong para village in Bandarban, Bangladesh: a case study." Journal of Biodiversity Conservation and Bioresource Management 5, no. 2 (January 15, 2020): 115–26. http://dx.doi.org/10.3329/jbcbm.v5i2.44922.
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The study was conducted to explore tree species diversity of Renikhayong para Village Common Forest (VCF) of Bandarban hill district. Stratified random sampling was carried out to assess the tree species diversity of the VCF. Renikhayong Para VCF with an area of 40 acres of land has more than 85 tree species belonging to 31 families, where Euphorbiaceae family was dominant containing 11 species followed by Rubiaceae (7 species), Moraceae (7 species), Meliaceae (5 species), Mimosaceae (5 species), Combretaceae (4 species), Lauraceae (4 species) and Anacardiaceae (3 species). Dominant tree species was Grewia nervosa. Renikhayong para VCF has diverse floristic resources that are known from the Shannon-Wiener’s diversity index (4.007), Simpson’s diversity index (0.028), Margalef’s richness index (13.21) and Species evenness index (0.90). However, number of species and number of individuals both were highest in the height range of 5 - <10 m. Similar trend was observed in dbh classes. Number of individuals were highest in dbh range of 5 - <15 cm and the lowest in ≥ 55 cm. The results depict the presence of maximum small trees in the VCF and decreasing the number of trees with the increase of tree height (m) and dbh (cm). Presence of diverse tree species and diversity indices indicate the importance and potential of the VCF for conservation and sustainable use.
J. Biodivers. Conserv. Bioresour. Manag. 2019, 5(2): 115-126
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AMBROSE, JR., WILLIAM G., PAUL E. RENAUD, SABINE K. J. COCHRANE, STANISLAV G. DENISENKO, and JOFRID SKARÐHAMAR. "Polychaete diversity patterns on two Arctic shelves: impacts of ice and primary production?" Zoosymposia 2, no. 1 (August 31, 2009): 457–85. http://dx.doi.org/10.11646/zoosymposia.2.1.33.
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We used data sets from two Arctic shelves to examine relationships between primary production (or a proxy), ice cover, and the diversity of polychaetes. Benthic samples were collected from the Northeast Water Polynya on the Northeast Greenland shelf and from the Barents Sea. Each of these areas is characterized by large differences in seasonal ice cover and primary production on a mesoscale. In addition to enumerating polychaete diversity, we also quantified the concentration of benthic algal pigments, sediment percent organic carbon, ice cover for the four years preceding sampling, and sediment grain size. In the Barents Sea, primary production was estimated from an ecosystem model. In both northeast Greenland and the Barents Sea, locations with lower primary production (Barents Sea) or proxies for primary production (benthic algal pigments: Greenland and Barents Sea), exhibited the greatest taxonomic richness. In Greenland, the area with the lowest concentration of benthic pigments had an ES(201) up to 30% higher than values from areas with four times more pigments. In the Barents Sea, ES(201) was greatest in the North under heaviest ice cover (>25% cover per year), again approximately 30% higher than in the South (<15% cover) or under the Polar Front (15–25% cover). Other factors also explained diversity: multiple regressions and Principal Component Analysis indicated that grain size, water depth and concentration of sediment organic carbon were important predictors of species diversity (Shannon-Wiener Index and Simpson’s Reciprocal Index), but the results of these analyses were occasionally different from the patterns observed in the species accumulation curves or ES(201) values. Simpson’s Index indicated that high ice-cover (and low primary production and benthic pigment) areas in the Barents Sea had greater evenness (lower dominance) than regions with higher indicators of food supply to the benthos. Low resource levels may prevent a few species from becoming very abundant and out-competing rare species. Diversity indices from northeast Greenland did not vary significantly among regions. We did not address habitat heterogeneity, but patchy distribution of food, combined with small- scale sediment heterogeneity also could enhance richness in food-poor areas. While the mechanism for the relationship between polychaete species richness and ice concentration or primary production is not clear, it does suggest that a change in polychaete diversity may need to be added to the list of possible responses of the benthos to climate-driven changes in ice cover.