Journal articles: 'Shannon's Diversity Index'

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Guiaşu, Radu Cornel, and Silviu Guiaşu. "Conditional and Weighted Measures of Ecological Diversity." International Journal of Uncertainty, Fuzziness and Knowledge-Based Systems 11, no. 03 (June 2003): 283–300. http://dx.doi.org/10.1142/s0218488503002089.

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Shannon's entropy and Simpson's index are the most used measures of species diversity. As the Simpson index proves to be just an approximation of the Shannon entropy, conditional Simpson indices of diversity and a global measure of interdependence among species are introduced, similar to those used in the corresponding entropic formalism from information theory. Also, since both the Shannon entropy and the Simpson index depend only on the number and relative abundance of the respective species in a given ecosystem, the paper generalizes these indices of diversity to the case when a numerical weight is attached to each species. Such a weight could reflect supplementary information about the absolute abundance, the economic significance, or the conservation value of the species.

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Cheng-Wen, Shen, Huang Yi-Huan, Huang Jian-An, Luo Jun-Wu, Liu Chun-Lin, and Liu De-Hua. "RAPD analysis on genetic diversity of typical tea populations in Hunan Province." Chinese Journal of Agricultural Biotechnology 5, no. 1 (April 2008): 67–72. http://dx.doi.org/10.1017/s147923620800199x.

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AbstractGenetic diversity and genetic variation of 240 adult plants of four tea populations in Hunan – Camellia sinensis var. sinensis, C. sinensis var. assamica cv. Duntsa, C. ptilophylla and C. sinensis var. assamica cv. Jianghua – were studied by rapid amplification of polymorphic DNA (RAPD) markers. The results showed 226 loci using 21 random primers (10 bp), of which 201 (88.9%) were polymorphic. The genetic diversity analysis indicated that Shannon's index was 0.43; 74.7% of which was within-population genetic diversity while 25.3% was among-population variation. The gene diversity indexes of total populations (HT), within populations (HS) and among populations (HST) were, respectively, 0.37, 0.28 and 0.09. The coefficient of gene differentiation (GST) among populations was 0.23, indicating a 76.7% variation within populations and 23.3% among populations. These results displayed a rich within-population genetic variation, as in Shannon's diversity index. Interpopulation gene flow (Nm) was 0.74, which indicates the limited genetic exchange between populations.

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Zhou, Ke, and Miao Miao Yan. "The Ineffectiveness of Landscape Diversity Index in Biocontrol: An Evidence from Small Scale Farmland." Applied Mechanics and Materials 295-298 (February 2013): 2675–78. http://dx.doi.org/10.4028/www.scientific.net/amm.295-298.2675.

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Landscape diversity index behaves ineffective in small scale farmland. The correlation coefficients between Shannon's diversity index as well as Simpson's diversity index with the population density of ladybeetles are negative. This result is opposite with the results from large scale farmland in developed countries. Landscape pattern has significant influence on the population density of ladybeetles. Especially the cotton/wheat relay intercrops have significant influence on the population density of ladybeetles. Besides grassland are also beneficial to the population density of ladybeetles.

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Łagód, Grzegorz, Mariola Chomczyńska, Agnieszka Montusiewicz, Jacek Malicki, and David Stransky. "Methods Applied for Measurement and Visualization of Changes in Biodiversity." Ecological Chemistry and Engineering S 21, no. 4 (February 2, 2015): 593–604. http://dx.doi.org/10.1515/eces-2014-0042.

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Abstract The article presents the possible methods for determining biological or statistically significant differences between taxocenoses compared with respect to biodiversity. To obtain a complete description of biological differences between the compared hypothetical communities, the following indices were calculated: S (taxon richness), H (the Shannon index), Hmax (the maximum value of the Shannon index for the richness of taxa represented by the same number of individuals), Vd (a percentage value of covering the structural capacity of community, “evenness deficiency”), E (the MacArthur index - a taxon number (S) in a community for which the observed value of H equals Hmax), and Ps (a taxon richness shortage in percents). Moreover, a graphic profile method (Дд, Tj, and Lj profiles) was used for comparing the diversity of the communities. To obtain information about statistically significant differences in biodiversity between the analysed communities, rarefaction curves were applied. The curves are based on the null models and the Monte Carlo method. The rarefaction method resulted in determination of the statistical significance of the differences between taxon richness and Shannon's index values for the compared communities. The Vd and Ps indices and the profile method allowed concluding about the significance of the biological differences between taxocenoses, even when their values of Shannon's H indices were numerically similar.

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Lee, Tsung Hung. "Ecological patterns of distribution on gradients of elevation and species diversity of snakes in southern Taiwan." Amphibia-Reptilia 26, no. 3 (2005): 325–32. http://dx.doi.org/10.1163/156853805774408522.

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AbstractThe study was conducted in southern Taiwan, along a road traversing the study area from 287 to 1680 m a.s.l. from May to October 2003 to investigate the distribution patterns and species diversity of the snakes. A total of 69 individual snakes belonging to 16 species were recorded. The Shannon's index and evenness index of the full study area were 2.4337 and 0.8777, respectively. Moreover, evenness index was 401 to 700 m > 1001 to 1300 m > 701 to 1000 m > 1301 to 1600 m altitudinal zone. The Shannon's index, DMG, and the reciprocal form of the Berger-Parker index (1/d) were 1001 to 1300 m > 401 to 700 m > 701 to 1000 m > 1301 to 1600 m altitudinal zone. Thirty-seven snakes were found in natural forest, 12 in plantation forest, 8 in secondary forest, and 12 in agricultural lands. I concluded that the highest species richness and diversity are found in mid-altitudinal mountains in southern Taiwan.

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Beisel, Jean-Nicolas, and Jean-Claude Moreteau. "A simple formula for calculating the lower limit of Shannon's diversity index." Ecological Modelling 99, no. 2-3 (June 1997): 289–92. http://dx.doi.org/10.1016/s0304-3800(97)01954-6.

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Fang, Gang, Jian Yong Chen, Juan Yang, Qiang Zhao, and Hai Min Su. "Dynamic Changes Analysis of Dangshan Landscape Pattern." Advanced Materials Research 356-360 (October 2011): 2870–73. http://dx.doi.org/10.4028/www.scientific.net/amr.356-360.2870.

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The article takes 2 TM images as the data source, supported by the Fragstats 3.3 and the ENVI 4.7 softwares, two remote sensing images are classified by the support vector machine method, selects the number of patches (NP), edge density (ED), patches density (PD), landscape shape index (LSI), perimeter area fractal dimension (PAFRAC), interspersion juxtaposition index (IJI), patch cohesion index (COHESION), Shannon's diversity index (SHDI), Shannon's evenness index (SHEI) and contagion index (CONTAG), using the landscape ecological principles and methods, analyzes the dynamic changes of Dangshan landscape patter in 1987-2009, with a view to Dangshan county land resources of reasonable planning and using, management, sustainable utilization, and the landscape pattern optimization configuration, provides the theory foundation and scientific basis.

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Sari, Indah Fitri, Nuning Nurcahyani, M. Kanedi, and Tugiyono Tugiyono. "Bird Species Diversity in Liwa Botanical Garden, West Lampung." Jurnal Ilmiah Biologi Eksperimen dan Keanekaragaman Hayati 7, no. 1 (April 1, 2020): 1–6. http://dx.doi.org/10.23960/jbekh.v7i1.5.

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The diversity of bird species can reflect the high biodiversity of an area. it means that birds can be used as a bio-indicator of environmental quality. Determining the quality and level ofenvironmental damage can be seen from the diversity of bird species in the region. Environmental quality will be better if the diversity of bird species in the region is diverse.Birds have an important role in protecting the ecosystem in the Liwa Botanical Garden. The presence of birds in the Liwa Botanical Garden has not been well identified. Therefore thisresearch needs to be done. This research was conducted on 12 October 2019 to 20 October 2019 in the Liwa Botanical Garden, West Lampung. Data collection of bird species isconducted in the morning at 06.30.00-08.30 West Indonesia Time and afternoon at 16.30-18.00 West Indonesia Time, with a combination of the count point and the transect method then all encounters with birds are recorded and identified directly at the study site. After the birds are identified, data is processed to find out Shannon's level index and diversity index. The species diversity index uses the Shannon and Weiner formula. The level of diversity is determined based on the species diversity index. The results showed that there were 15 bird species with a total of 466 individuals with a moderate diversity index and an evenness index indicating a distressed community.

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Holland, David N., Robert J. Lilieholm, David W. Roberts, and J. Keith Gilless. "Economic trade-offs of managing forests for timber production and vegetative diversity." Canadian Journal of Forest Research 24, no. 6 (June 1, 1994): 1260–65. http://dx.doi.org/10.1139/x94-165.

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Three indices of forest stand structural and compositional diversity were incorporated into a linear programming timber harvest scheduling model to examine the trade-offs between managing stands for timber production and biodiversity objectives. The indices, based on Shannon's diversity index, characterized stand species diversity, basal area diversity, and vertical crown diversity. While harvest-level objectives were often compatible with the maintenance of vegetative diversity, the maximization of present net value was accompanied by substantial reductions in all three measures of diversity.

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Liang, Yu, Jian Liu, Shu Ping Zhang, Shu Jun Wang, Wei Hua Guo, and Ren Qing Wang. "Genetic diversity of the invasive plant Coreopsis grandiflora at different altitudes in Laoshan Mountain, China." Canadian Journal of Plant Science 88, no. 4 (July 1, 2008): 831–37. http://dx.doi.org/10.4141/cjps07020.

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In order to understand the relationship between genetic diversity and the invasiveness of exotic plants, genetic diversity was studied in the invasive plant Coreopsis grandiflora Hogg. at different altitudes in Laoshan Mountain, Northern China. Coreopsis grandiflora has produced a great deal of damage in Laoshan Mountain. Its genetic diversity was examined using 16 random amplified polymorphic DNA (RAPD) primers, and 125 bands were collected from all individuals. The mean percentage of polymorphic loci (P%) was 39.54%, and the total percentage of polymorphic loci (P%) was 86.40%. The mean Shannon's Information index (H0) was 0.2326 and the mean Nei's genetic diversity (H) was 0.1596. These results indicated a comparatively high genetic diversity in C. grandiflora in Laoshan Mountain. The genetic differentiation among populations (GST) was 0.3948, indicating that most genetic diversity occurs within populations. On the whole, the abundance and the genetic diversity of C. grandiflora decreased with increasing altitude. The high genetic diversity may be related to the invasion of C. grandiflora in Laoshan Mountain. Key words: Biological invasions, Coreopsis grandiflora Hogg., genetic distance, genetic diversity, random amplified polymorphic DNA (RAPD), sexual reproduction, Shannons information index

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Markovic, Goran, and Predrag Veljovic. "Biotic indices to be used for assessment of Ichthyofauna structure of the Zapadna Morava river (West Serbia, the Danube basin)." Zbornik Matice srpske za prirodne nauke, no. 109 (2005): 29–37. http://dx.doi.org/10.2298/zmspn0519029m.

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The presence of 25 fish species from 8 families was found to exist in the ichthyofauna of the Zapadna Morava river (the Danube basin, West Serbia) in the period from 1996-1999. The structure of the fish community was analysed using a substantial number of indices (Shannon's index - diversity Margalef's index of diversity, Sorensen's index of biotic similarity and Saprobic index of community). Qualitative-quantitative relationships in the ichthyofauna of the 4 river and one lake profiles were compared, too. High differences due to diversity in the general environmental conditions existing in the individual habitats were also established. An excessively high antropogenous impact on the diversity of aquatic ecosystems gave rise not only to a deteriorated water quality, but also to an abundance of the allochthonous ichthyofauna representatives.

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Niese, Jeffrey Neal, and Terry F. Strong. "Economic and tree diversity trade-offs in managed northern hardwoods." Canadian Journal of Forest Research 22, no. 11 (November 1, 1992): 1807–13. http://dx.doi.org/10.1139/x92-236.

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Forest ecologists have long believed that greater tree species diversity in hardwood forests reduces biological risk, but researchers have not yet linked diversification with economic returns for managed hardwood forests. This paper shows how management of northern hardwood forests affects tree species diversity and economic returns. Shannon's index is used to measure regeneration diversity for eight even- and uneven-aged cutting methods from a 40-year study on the Argonne Experimental Forest. These indices of tree species diversity are compared with the potential economic returns for the research sites.

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Duan, C. X., W. C. Li, Z. D. Zhu, D. D. Li, S. L. Sun, and X. M. Wang. "Genetic differentiation and diversity of Callosobruchus chinensis collections from China." Bulletin of Entomological Research 106, no. 1 (November 9, 2015): 124–34. http://dx.doi.org/10.1017/s0007485315000863.

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AbstractCallosobruchus chinensis (Linnaeus) is one of the most destructive pests of leguminous seeds. Genetic differentiation and diversity analysis of 345 C. chinensis individuals from 23 geographic populations using 20 polymorphic simple sequence repeats revealed a total of 149 alleles with an average of 7.45 alleles per locus. The average Shannon's information index was 1.015. The gene flow and genetic differentiation rate values at the 20 loci ranged from 0.201 to 1.841 and 11.0–47.2%, with averages of 0.849 and 24.4%, respectively. In the 23 geographic populations, the effective number of alleles and observed heterozygosity ranged from 1.441 to 2.218 and 0.191–0.410, respectively. Shannon's information index ranged from 0.357 to 0.949, with the highest value in Hohhot and the lowest in Rudong. In all comparisons, the fixation index (FST) values ranged from 0.049 to 0.441 with a total FST value of 0.254 among the 23 C. chinensis populations, indicating a moderate level of genetic differentiation and gene flow among these populations. Analysis of molecular variance revealed that the genetic variation within populations accounted for 76.7% of the total genetic variation. The genetic similarity values between populations varied from 0.617 to 0.969, whereas genetic distances varied from 0.032 to 0.483. Using unweighted pair-group method using arithmetical averages cluster analysis, the 23 geographic collections were classified into four distinct genetic groups but most of them were clustered into a single group. The pattern of the three concentrated groups from polymerase chain reactions analysis showed a somewhat different result with cluster.

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Moreira, Milene, Dilmar Baretta, Siu Mui Tsai, Sandra Maria Gomes-da-Costa, and Elke Jurandy Bran Nogueira Cardoso. "Biodiversity and distribution of arbuscular mycorrhizal fungi in Araucaria angustifolia forest." Scientia Agricola 64, no. 4 (August 2007): 393–99. http://dx.doi.org/10.1590/s0103-90162007000400010.

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Araucaria angustifolia (Bert.) O. Ktze. is an endangered Brazilian coniferous tree that has been almost exterminated in the native areas because of uncontrolled wood exploitation. This tree has been shown to be highly dependent on arbuscular mycorrhizal fungi (AMF) and, therefore, AMF may be essential for forest sustainability and biological diversity. Root colonization, density and diversity of AMF spores were assessed in two Araucaria forest stands at the State Park of Alto Ribeira (PETAR), at two sampling dates: May and October. A comparison was made between a mature native stand composed of Araucaria trees mixed into a variety of tropical trees and shrubs, without any sign of anthropogenic interference (FN) and an Araucaria stand planted in 1987 (R), which has been used as a pasture. Assessments included percent root colonization, AMF spore numbers and species richness, Simpson's dominance index (Is), and Shannon's diversity index (H). Mycorrhizal root colonization did not differ between ecosystems in May. In October, however, the native stand (FN) presented a higher colonization than the planted forest (R), and the root colonization was more intense than in May. When considering both sampling periods and forests, 27 species of AM fungi, with higher numbers of spores in FN than in R were found. Canonical discriminant analysis (CDA) indicated Shannon's diversity index as the ecological attribute that contributed the most to distinguish between forest ecosystems, with higher value of H in FN in relation to R. CDA showed to be a useful tool for the study of ecological attributes.

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Setotaw, Tesfahun Alemu, Eveline Teixeira Caixeta, Guilherme Ferreira Pena, Eunize Maciel Zambolim, Antonio Alves Pereira, and Ney Sussumu Sakiyama. "Breeding potential and genetic diversity of "Híbrido do Timor" coffee evaluated by molecular markers." Crop Breeding and Applied Biotechnology 10, no. 4 (December 2010): 298–304. http://dx.doi.org/10.1590/s1984-70332010000400003.

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AFLP, RAPD and SSR molecular markers were used to study the genetic diversity and genetic structure of the Híbrido de Timor germplasm. The principal coordinate analysis, UPGMA cluster analysis based on genetic dissimilarity of Jaccard, Bayesian model-based cluster analysis, percentage of polymorphic loci, Shannon's information index and Nei gene diversity were employed to assess the genetic diversity. The analyses demonstrated a high genetic diversity among Híbrido de Timor accessions. UPGMA and Bayesian cluster analyses grouped the accessions into three clusters. The genetic structure of Híbrido de Timor is reported. The management of Híbrido de Timor germplasm variability and its potential use in breeding programs are discussed.

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Barbieri Junior, CA, and AMP Dias. "Braconidae (Hymenoptera) fauna in native, degraded and restoration areas of the Vale do Paraíba, São Paulo state, Brazil." Brazilian Journal of Biology 72, no. 2 (May 2012): 305–10. http://dx.doi.org/10.1590/s1519-69842012000200011.

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This study sampled the diversity of Braconidae (Hymenoptera) in three different ecosystems: a degraded pasture, a secondary forest and an area in recovery process using native tree seedlings. The objective was to verify the use of those insects as a tool to check the local conservation by examining Shannon's diversity index. Ten subfamilies were identified, and Microgastrinae was predominant in a number of individuals. The diversity index calculated varies among the sampled areas, thus showing a correlation with vegetation cover with the number of individuals collected and number of subfamilies found. The results showed changes in the community of Braconidae, in the recovery area between the first and second year of study, thereby leading to the conclusion that they are indicators of environmental quality.

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Jaradat, A. A., and M. Shahid. "Population and multilocus isozyme structures in a barley landrace." Plant Genetic Resources 4, no. 2 (August 2006): 108–16. http://dx.doi.org/10.1079/pgr2005105.

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Isozyme data were used to assess genetic diversity within and among a subdivided population of the salt-tolerant Batini barley landrace. Population diversity and its components were estimated on the basis of 12 isozymes scored on 450 single plants representing seven subpopulations. Two principal components, based on mean gene diversity, Shannon's diversity index, percentage polymorphic loci, genetic identity and genetic distance among subpopulations accounted for 91.7% of total variation and separated the subpopulations into four distinct groups. Contributions to total diversity by individual subpopulations were partitioned into intra- and inter-population components. The level of population differentiation indicates that a large percentage of total genetic diversity was apportioned within subpopulations. The presence of valuable genetic diversity in this landrace was confirmed.

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Ricotta, C., M. L. Carranza, G. Avena, and C. Blasi. "Quantifying the deviation of landscape diversity from potential natural vegetation with Shannon's entropy." Geobotanical mapping, no. 2001-2002 (2002): 23–31. http://dx.doi.org/10.31111/geobotmap/2001-2002.23.

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In the past 20 years, several metrics have been developed to quantify various aspects of landscape structure and diversity in space and time, and most have been tested on grid- based thematic maps. Once landscape patterns have been quantified, their effects on ecological functions can be explained if the expected pattern in the absence of specific processes is known. This type of expected pattern has been termed a neutral landscape model. In the landscape-ecological literature, researchers traditionally adopt random and fractal computer-generated neutral landscape models to verify the expected relationship between a given ecological process and landscape spatial heterogeneity. Conversely, little attention has been devoted to distribution patterns of potential natural vegetation (PNV) as an ecological baseline for the evaluation of pattern-process interactions at the landscape scale. As an application for demonstration, we propose a neutral model based on PNV as a possible reference for a quantitative comparison with actual vegetation (ARV) distribution. Within this context, we introduce an evenness-like index termed "actual-to-potential entropy ratio’ (HA/P=HARV/HPNV, where H is Shannon’s entropy). Results show that, despite the hypothetical character of most PNV maps, the use of PNV distribution as a baseline for a quantitative comparison with ARV distribution may represent a first step towards г general model for the evaluation of the effects of disturbance on vegetation patterns and diversity.

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Abolghasem Mohammadi, Seyed, Majid Shokrpour, Mohammad Moghaddam, and Aziz Javanshir. "AFLP-based molecular characterization and population structure analysis of Silybum marianum L." Plant Genetic Resources 9, no. 3 (April 18, 2011): 445–53. http://dx.doi.org/10.1017/s1479262111000645.

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Amplified fragment length polymorphism analysis was employed to investigate the population structure of 32 Iranian Silybum marianum populations along with two commercial varieties. A total of 415 polymorphic marker loci were produced by 27 primer combinations with an average of 15.37 markers per combination. Polymorphic information content ranged from 0.24 to 0.44 with an average of 0.35 per primer combination, and marker index was in the range of 2.56–9.50 with an average of 5.37. The average Nei's genetic diversity (HE) and Shannon's diversity index (I) were 0.201 and 0.296, respectively. The coefficient of differentiation among populations (GST) was 0.44, indicating that 44% of the total molecular diversity resulted from differences between populations. We identified three major groups based on cluster analysis and principal coordinate analysis, which were mostly in concordance with the geographical grouping of the populations. The molecular diversity estimate could be useful for selecting appropriate populations to improve S. marianum through conventional and molecular breeding.

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Espino Barranco, Laura Elena, Martín Aubert Hernández Calzada, and Carla Carolina Pérez Hernández. "Diversification of the financial education needs of the entrepreneurial ecosystem: a multidimensional scaling analysis applied to data from a financial intelligence platform." Journal of Administrative Science 3, no. 5 (July 5, 2021): 17–22. http://dx.doi.org/10.29057/jas.v3i5.6770.

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The objective of this research is to analyze the financial education needs of the central region of the country through Non-Parametric Multidimensional Scaling (NMDS), Shannon's diversity index and Simpson's dominance index, applied to a database from of a financial intelligence technological platform to identify the similarity of financial needs among users and their financial preferences. The results obtained show similarity between the data, which indicates that there is a lack of financial knowledge in the entrepreneurial ecosystem and, therefore, a high death rate of SMEs and uninformed financial decisions based on errors of interpretation of the information.

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Gorelick, Root. "Combining richness and abundance into a single diversity index using matrix analogues of Shannon's and Simpson's indices." Ecography 29, no. 4 (August 2006): 525–30. http://dx.doi.org/10.1111/j.0906-7590.2006.04601.x.

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Bayat, Mahdi, Reza Amirnia, Hakan Özkan, Aysun Gedik, Duygu Ates, Bahattin Tanyulac, and Mehdi Rahimi. "Diversity and phylogeny of saffron (Crocus sativus L.) accessions based on iPBS markers." Genetika 50, no. 1 (2018): 33–44. http://dx.doi.org/10.2298/gensr1801033b.

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This study sought to measure genetic diversity and phylogenetic structure among 196 individuals of saffron from 20 geographically separate accessions from Iran, Spain and Turkey using retrotransposon derived iPBS markers. Twenty-eight primers amplified a total of 179 polymorphic alleles with an average of 6.4 bands per primer. The average of parameters shannon's information index, genetic distance and gene diversity was 0.483, 0.286 and 0.841 respectively. Polymorphic information index ranged from 0.407 to 0.953 with an average of 0.824. Primers 2298, 2229 and 2393 with 0.953, 0.943 and 0.943 PIC respectively, identified as the most informative primers in this study. The results of phylogenetic trees showed that twenty saffron accessions were placed into four major clusters that matched with their geographical locations completely. These results are supported by principal coordinate analysis. Overall, we can confirm that iPBS markers as low cost and high efficient molecular markers are a powerful DNA fingerprinting for assessing genetic diversity and phylogenetic analysis among saffron accessions originating from different geographical regions.

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Varga, Pàl, Han YH Chen, and Karel Klinka. "Tree-size diversity between single- and mixed-species stands in three forest types in western Canada." Canadian Journal of Forest Research 35, no. 3 (March 1, 2005): 593–601. http://dx.doi.org/10.1139/x04-193.

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Mixed-species stands are hypothesized to be more structurally diverse because of inherent differences in growth rates between tree species. We investigated three combinations of even-aged, single- and mixed-species coniferous stands in western Canada: (i) shade-tolerant western hemlock (Tsuga heterophylla (Raf.) Sarg.) and western redcedar (Thuja plicata (Donn ex D. Don) Spach), (ii) shade-intolerant lodgepole pine (Pinus contorta Dougl. ex Loud.) and western larch (Larix occidentalis Nutt.), and (iii) shade-intolerant lodgepole pine and shade-tolerant black spruce (Picea mariana (Mill.) BSP). We quantified stand structural diversity based on tree diameter and height by using Shannon's index and the coefficient of variation. Regression analysis was applied to examine the relationships between structural diversity, species composition, and stand age. Mixed-species stands of western hemlock and western redcedar had similar structural diversity to their respective single-species stands. Pinelarch and pinespruce mixed-species stands had higher tree-size diversity than their respective single-species stands. Stand age was a significant factor for tree-size diversity, but its effect changed in different ways depending on the type of mixtures and index used to measure diversity.

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Bourguiba, Hedia, Mohamed-Amine Batnini, Lamia Krichen, Neila Trifi-Farah, and Jean-Marc Audergon. "Population structure and core collection construction of apricot (Prunus armeniaca L.) in North Africa based on microsatellite markers." Plant Genetic Resources 15, no. 1 (July 31, 2015): 21–28. http://dx.doi.org/10.1017/s1479262115000313.

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North Africa enclosed original apricot genetic resources with the cohabitation of grafting and seed-propagated accessions. In this study, we assessed the genetic diversity and population structure of 183 apricot accessions using 24 microsatellite markers distributed evenly in the Prunus genome. A total of 192 alleles and a high level of gene diversity (0.593) were detected among the whole panel. Genetic structure analysis revealed the presence of four genetic clusters. We also found that both geographical origin and mode of propagation are important factors structuring genetic diversity in apricot species. Results confirmed the presence of gene exchange between the northern and southern countries of the Mediterranean Basin. Subsequently, a core collection of 98 accessions based on M (maximization) strategy showing 99.47% of allele retention ratio was constructed. No significant differences for Shannon's information index and Nei's diversity index were observed between the core and entire collections. Our results provide an effective aid for future germplasm preservation and conservation strategies as well as genetic association studies development in relation to phenotypic data.

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Nykytiuk, P., V. Moroz, and O. Komorna. "Species diversity indices in poultry farms insect communities." Ukrainian Journal of Ecology 10, no. 6 (December 10, 2020): 66–68. http://dx.doi.org/10.15421/2020_259.

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Chicken farms need to improve existing and introduce new technologies for the construction of appropriate wastewater treatment plants and processing of solid manure, which will ensure proper treatment of waste before it enters the environment. The results of determining the ecological indices of the sanitary protection zone of poultry farms indicate their negative impact on the biological diversity and richness of insect groups. In particular, the value of the Margalef species richness index is 25% less in the special protected zones in farms, compared to the control area, and the value of Shannon's species diversity by 12%. Further reduction of species diversity may lead to rapid degradation of ecosystems adjacent to the area of poultry farms. The assessment of taxonomic diversity, complexity of insect groups and their competitive structure in the area of poultry production proved the inverse relationship between the percentage of eudominants and sub-precedents, as well as the predominance of the percentage of precedents over the percentage of dominant.

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Rufai, Shamsuddeen, M. M. Hanafi, M. Y. Rafii, S. Ahmad, I. W. Arolu, and Jannatul Ferdous. "Genetic Dissection of New Genotypes of Drumstick Tree (Moringa oleiferaLam.) Using Random Amplified Polymorphic DNA Marker." BioMed Research International 2013 (2013): 1–6. http://dx.doi.org/10.1155/2013/604598.

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The knowledge of genetic diversity of tree crop is very important for breeding and improvement program for the purpose of improving the yield and quality of its produce. Genetic diversity study and analysis of genetic relationship among 20Moringa oleiferawere carried out with the aid of twelve primers from, random amplified polymorphic DNA marker. The seeds of twentyM. oleiferagenotypes from various origins were collected and germinated and raised in nursery before transplanting to the field at University Agricultural Park (TPU). Genetic diversity parameter, such as Shannon's information index and expected heterozygosity, revealed the presence of high genetic divergence with value of 1.80 and 0.13 for Malaysian population and 0.30 and 0.19 for the international population, respectively. Mean of Nei's gene diversity index for the two populations was estimated to be 0.20. In addition, a dendrogram constructed, using UPGMA cluster analysis based on Nei's genetic distance, grouped the twentyM. oleiferainto five distinct clusters. The study revealed a great extent of variation which is essential for successful breeding and improvement program. From this study,M. oleiferagenotypes of wide genetic origin, such as T-01, T-06, M-01, and M-02, are recommended to be used as parent in future breeding program.

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Lopes, Jocelly De Sousa, Márcia Regina Jantsch Da Costa, and Daniele Aparecida Alvarenga Arriel. "Genetic diversity of potential mother trees of Myracrodruon urundeuva by ISSR markers." Advances in Forestry Science 7, no. 2 (June 28, 2020): 1017–24. http://dx.doi.org/10.34062/afs.v7i2.9424.

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Myracrodruon urundeuva is a tree species of the family Anacardiaceae, native from the northeast, southeast and midewest regions of Brazil, locally known as aroeira. Because of its long history of predatory exploitation, this species is has been lately classified as vulnerable to extinction. The present work had as objective to evaluate the genetic diversity of potential mother trees of M. urundeuva using ISSR molecular markers in order to subsidize the collection of seeds with large genetic diversity. The selected trees are located in the forest reserve of Brita Guia, in the municipality of Cuiabá – MT, Brazil. Of the 20 ISSR primers tested, seven were selected to characterize genetic variability. The total amplified fragments were 116, with a percentage of 99.15% polymorphism. The individuals presented Nei's genetic diversity (He) of 0.2706 and Shannon's diversity index (I) of 0.4226. The UPGMA grouping method revealed the existence of two large groups among the individuals, which could be considered to perform seed collection among divergent genotypes.

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Uuemaa, Evelyn, Jüri Roosaare, and Ülo Mander. "Landscape metrics as indicators of river water quality at catchment scale." Hydrology Research 38, no. 2 (April 1, 2007): 125–38. http://dx.doi.org/10.2166/nh.2007.002.

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We investigated the relationship between land use parameters and FRAGSTATS-based landscape metrics (Edge Density, Patch Density, Mean Shape Index, Mean Euclidean Nearest Neighbour Index, Contagion, Patch Richness Density and Shannon's Diversity Index) and nutrient/organic-matter-based water quality indicators (BOD7 and CODKMnO4 values, total-N and total-P concentrations in water) in 24 catchments with various land use patterns in Estonia, using the CORINE Land Cover Map (1:100 000). Multiple regression analysis showed that, for BOD7, total-N and total-P, the most important predictor was the proportion of urban areas, but landscape metrics also had a significant relationship with water quality. Mean Shape Index and Contagion were the most important predictors for CODKMnO4. The knowledge that land use and landscape configuration impact water quality can be used in establishing and implementing water management plans in Europe.

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Cunha Neto, Felipe Vieira da, Maria Elizabeth Fernandes Correia, Guilherme Henrique Almeida Pereira, Marcos Gervasio Pereira, and Paulo Sérgio dos Santos Leles. "Soil fauna as an indicator of soil quality in forest stands, pasture and secondary forest." Revista Brasileira de Ciência do Solo 36, no. 5 (November 2012): 1407–17. http://dx.doi.org/10.1590/s0100-06832012000500004.

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The interactions between soil invertebrates and environmental variations are relatively unknown in the assessment of soil quality. The objective of this study was to evaluate soil quality in areas with different soil management systems, based on soil fauna as indicator, in Além Paraíba, Minas Gerais, Brazil. The soil invertebrate community was sampled using pitfall traps, in the dry and rainy seasons, from areas with five vegetation types (acacia, mimosa, eucalyptus, pasture, and secondary forest). The abundance of organisms and the total and average richness, Shannon's diversity index, the Pielou uniformity index, and change index V were determined. The fauna was most abundant in the areas of secondary forest and mimosa plantations in the dry season (111.3 and 31.7 individuals per trap per day, respectively). In the rainy season, the abundance of organisms in the three vegetation types did not differ. The highest values of average and total richness were recorded in the secondary forest in the dry season and in the mimosa stand in the rainy season. Shannon's index ranged from 1.57 in areas with acacia and eucalyptus in the rainy season to 3.19 in the eucalyptus area in the dry season. The uniformity index was highest in forest stands (eucalyptus, acacia and mimosa) in the dry season, but higher in the rainy season in the pasture and secondary forest than in the forest stands. The change index V indicated that the percentage of extremely inhibited groups was lowest in the area with mimosa, both in the dry and rainy season (36 and 23 %, respectively). Of all forest stands, the mimosa area had the most abundant soil fauna.

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Jakob, Eva, Reinhold Hanel, Sven Klimpel, and Karsten Zumholz. "Salinity dependence of parasite infestation in the European eel Anguilla anguilla in northern Germany." ICES Journal of Marine Science 66, no. 2 (September 25, 2008): 358–66. http://dx.doi.org/10.1093/icesjms/fsn160.

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Abstract Jakob, E., Hanel, R., Klimpel, S., and Zumholz, K. 2009. Salinity dependence of parasite infestation in the European eel Anguilla anguilla in northern Germany. – ICES Journal of Marine Science, 66: 358–366. The aim of the study was to examine metazoan parasite communities of European eels (Anguilla anguilla) in fresh-water, brackish water and marine localities in northern Germany. In all, 29 parasite species/taxa were found in 170 eels: eight digeneans, one monogenean, five cestodes, ten nematodes, two acanthocephalans, and three crustaceans. Measures of diversity characteristics of the helminth communities included species richness, Shannon's diversity index and its evenness, and the Berger–Parker dominance index. The highest species diversity and lowest dominance values were calculated for the helminth communities of eels from the two Baltic Sea localities. Parasite communities of European eels clearly exhibit the habitat preferences of their hosts, salinity-dependent specificities, and a clustering into fresh-water, brackish, and marine groups. The highly pathogenic parasite species Anguillicola crassus and Pseudodactylogyrus spp. were found at all sampling sites in fresh water and brackish water, with high prevalence. Basic information is provided on the risks of restocking programmes solely focusing on fresh-water sites.

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Dutoit, T., P. Roche, and D. Alard. "Influence de perturbations anthropiques sur la composition et la diversité botanique des pelouses calcicoles de la vallée de la Seine en Haute-Normandie (France)." Canadian Journal of Botany 77, no. 3 (August 20, 1999): 377–88. http://dx.doi.org/10.1139/b98-231.

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The effects of two types of anthropic disturbances (reaping and plowing) were followed over 3 years, on four calcicolous meadows of the Seine valley (Haute-Normandie) in France, using the quadrat points method. Multivariate analysis performed on the overall data show that compositions and structures of the different plant communities are mainly influenced by the site geographic position along an ecological gradient developing from the Seine river estuary toward the uppper stream of the river. Over the 3 years of observation, a significant increase of the species diversity (Shannon's index) and richness was observed in the reaped plots compared with the plots that were abandoned after disturbances. However, there was no significant difference between the two treatments in the species diversity as well as richness. Results are discussed in view of conservative management of calcicolous meadows, since these seminatural ecosystems are especially threatened in Western Europe.Key words: calcicolous meadows, disturbances, species diversity and richness, conservation, Haute-Normandie, France.[Journal translation]

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Herbst, Helge, Michael Förster, and Birgit Kleinschmit. "Contribution of landscape metrics to the assessment of scenic quality - the example of the landscape structure plan Havelland/Germany." Landscape Online 10 (March 16, 2009): 1–17. http://dx.doi.org/10.3097/lo.200910.

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The scenic quality of a landscape is a natural resource that is to be preserved according to German and international law. One important indicator for the evaluation of this value is the structural diversity of the landscape. Although Landscape Metrics (LM) represent a well-known instrument for the quantification of landscape patterns, they are hardly used in applied landscape and environmental planning. This study shows possibilities for the integration of LM into a commonly used method to assess scenic quality by the example of a Landscape Structure Plan. First results indicate that especially Shannon's Diversity Index and Edge Density are suitable to achieve an objective evaluation of the structural diversity as indicator for scenic quality. The addition of qualitative parameters to the objective structural analysis is discussed. Moreover, the use of landscape scenery units and raster cells as basic geometry has been compared. It shows that LM can support the evaluation of the aesthetic quality in environmental planning, especially when integrated into commonly used evaluation methods.

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Albert, T., O. Raspé, and A. L. Jacquemart. "Diversity and spatial structure of clones in Vaccinium uliginosum populations." Canadian Journal of Botany 83, no. 2 (February 1, 2005): 211–18. http://dx.doi.org/10.1139/b04-164.

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In Belgium, a total of three Vaccinium species with a shrub or dwarf shrub growth form can be found: Vaccinium myrtillus L., Vaccinium vitis-idaea L., and Vaccinium uliginosum L. Vaccinium uliginosum is the only one of these for which the extent of clonality is unknown. Therefore, the clonal structure of two V. uliginosum populations was inferred from random amplified polymorphic DNA (RAPD) markers. Among the 47 sampled patches, 61 clones were identified. The mean values of the number of clones divided by the number of samples (G/N), the Simpson's index (D), and the genotypic evenness (E) were 0.28, 0.95, and 0.96, respectively. Vaccinium uliginosum exhibited a typical phalanx growth strategy that resulted in structured populations at the ramet level, that is, ramets belonging to the same clone were closely associated and formed distinct clumps. However, at the clone level, populations were not structured, that is, genetic distances between pairs of clones were not correlated with the spatial distances between the clones within a population. Genetic diversity was as high as that in nonclonal species (mean value of Shannon's diversity index (Ho) = 0.647). In accord with the life history traits of V. uliginosum (long-lived species with a mixed breeding system and potentially high seed dispersal), most of the genetic variation was found within populations.Key words: genetic diversity, genetic structure, seedling recruitment, vegetative propagation, Ericaceae.

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Mohammad Kanedi, Nismah Nukmal, Gina Dania Pratami, and Hajariyah. "Impact of ground cover vegetation types on the diversity and similarity of spider assemblage at two adjacent sites." GSC Advanced Research and Reviews 8, no. 1 (July 30, 2021): 060–65. http://dx.doi.org/10.30574/gscarr.2021.8.1.0144.

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Spider (Arachnida) is one of the classes of arthropods known to give strong responses to differences in land cover vegetation. This study intended to investigate whether the difference of vegetation types that are located adjacently occupied by the same genera of spiders. Two adjacent areas in Liwa Botanical Garden that covered by two different types vegetation were assigned as the sampling sites. The spiders sampling was carried out over a 100 meter long transect line (5 lines each) by applying active searching and pitfall trapping techniques. There were 21 genera from 9 spider families that were collected from two sampling sites. In the land vegetated with wood, there were 12 genera with 129 specimens. In the herbaceous land, there were 13 spider genera with 120 specimens. The Simpson's index of diversity were 0.7739 and 0.8868, meanwhile the Shannon's index were 1.8575and 2.2831, respectively obtained at herbaceous and woody land. The difference of diversity between two compared sites by Hutcheson t-test was highly significant (α < 0.01). This presumption is also supported by the coefficient of dissimilarity calculated using Sorensen’s index formula (Ss = 75.7575). Thus it can be concluded that the different types of land cover vegetation have a significant impact on the diversity of the dwelling spiders even though the two fields are located adjacent to each other.

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Abdul Kareem, V. K., P. E. Rajasekharan, S. Mini, and T. Vasantha Kumar. "Genetic diversity and structure of the threatened anti-cancerous plantNothapodytes nimmonianaas revealed by ISSR analysis." Plant Genetic Resources 9, no. 4 (July 22, 2011): 506–14. http://dx.doi.org/10.1017/s1479262111000803.

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Inter simple sequence repeat markers were used to assess the genetic diversity and population genetic structure in 12 populations ofNothapodytes nimmonianafrom Western Ghats of India. A total of 16 selected primers produced 103 discernible bands, with 76 (73.7%) being polymorphic. The Nei's gene diversity (h) ranged from 0.1166 to 0.2124, with an average of 0.1518 at the population level and 0.2965 at the species level indicating high genetic diversity. The Shannon's index (I) was estimated to be 0.2189 within populations (range 0.1703–0.2947) and 0.4352 at the species level. The analysis of molecular variance showed that the genetic variation was found mainly within populations (73%), but variance among populations was only 27% and its value, ΦPT = 0.271,P < 0.001, implied that high genetic differentiation among populations. In addition, Nei's differentiation coefficient (GST) was found to be high (0.4882) and the gene flow (Nm) was low (0.5242), confirming the high population genetic differentiation. The unweighted pair-group method using arithmetic average clustering elicited similar results. Based on this, we propose conservation strategy for this plant species.

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Khoshsokhan, F., M. Babalar, M. Fatahi, and A. Poormeidani. "Assessment of Genetic Diversity of Some Wild Populations of Thymus Kotschyanus Usingrapd Molecular Markers." Cercetari Agronomice in Moldova 47, no. 3 (September 1, 2014): 71–81. http://dx.doi.org/10.2478/cerce-2014-0028.

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Abstract RAPD molecular markers were used to assess the genetic diversity of some population of thyme (Thymus kotschyanus) from Iran. The 17 tennucleotide primers used that produced 185 high-resolution bands, which 21 of these were monomorphic and 162 were polymorphic. An average, 10.88 bands were obtained per primer and 9.52 of these were polymorphic. POPGENE software was used to calculate Nei's genetic distance among populations and based on the cluster analysis of this matrix, a UPGMA dendrogram was drawn using the software NTSYS-pc. On the basis of dendrogram among populations of wild mountain thyme, Avan (Qazvin) and Siahkal (Gilan province) populations was the most similar between studied populations with the distance of 0.094 high disimilarity was observed between Qazvin and Mazandaran 2 populations with the distance of 0.185 within populations variation based on Shannon's information index and Nei genetic diversity index showed that Takestan (I= 0.26; H= 0.3) and Alamut (I= 0.24; H= 0.15) had a highest and lowest within populations variation compared to other populations, respectively. Average of Fst and Nm indices, which represent the amount of gene flow between populations, were recorded as 0.26 and 1.361, respectively, which reflects the high level of gene exchange between ten populations of Thymus kotschyanus.

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ALLNUTT, T. R., J. R. COURTIS, M. GARDNER, and A. C. NEWTON. "GENETIC VARIATION IN WILD CHILEAN AND CULTIVATED BRITISH POPULATIONS OF PODOCARPUS SALIGNUS D. DON (PODOCARPACEAE)." Edinburgh Journal of Botany 58, no. 3 (October 24, 2001): 459–73. http://dx.doi.org/10.1017/s0960428601000774.

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The threatened Chilean conifer Podocarpus salignus D. Don is currently the focus of ex situ conservation eorts being undertaken by the Conifer Conservation Programme of the Royal Botanic Garden Edinburgh. To assess variation within in and ex situ populations of the species, leaf material collected from four wild populations was analysed by random amplified polymorphic DNA (RAPD). Amova of RAPD profiles indicated that 93% of the variation occurred within, rather than between, populations. Intraspecific genetic diversity, estimated using percentage polymorphic loci, Shannon's diversity index, and Nei's gene diversity, was relatively high (47%, 0.692 and 0.314, respectively). To assess genetic diversity in ex situ populations within the UK, RAPD analysis of parents and progeny at two Cornish arboreta was undertaken. The results provided evidence of novel hybridization with suspected paternal trees (P. hallii Kirk and P. totara G. Benn. ex D. Don) endemic to New Zealand. RAPD was found to be an effective tool for assessing the genetic structure of P. salignus, for providing a guide to future germplasm-sampling strategies, and for hybrid identification. Implications for genetic conservation of the species and the role of ex situ approaches are discussed.

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Yun-xia, Chen, Jiang Jun-fan, Nan Cheng-hui, and Xue Xiao-ming. "ISSR Analysis on Genetic Diversity of Endangered Plant Parrotia subaequalis in Dalonggou of Yixing, Jiangsu." E3S Web of Conferences 145 (2020): 01026. http://dx.doi.org/10.1051/e3sconf/202014501026.

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In this study, 25 flower samples of Parrotia subaequalis individuals were collected in Dalonggou of Yixing, Jiangsu. ISSR markers were used to analyze the genetic diversity of the 25 individuals. Six primers were selected and used for PCR amplification. The result showed that 59 discernible DNA fragments were amplified, among them 47 are polymorphic loci and the percentage of polymorphic loci (PPB) is 79.7%. By analysis with POPGENE32, the effective number of alleles (Ne) is 1.4697, Nei's gene diversity (H) is 0.2792, Shannon's Information index (I) is 0.4195, the Ewens-Watterson Neutral value is between 0.02 to 1, and more than half of the neutral test values are above 0.5. Through cluster analysis with NTSYSpc-2.1, genetic similarity coefficients of 25 samples are between 0.25 and 1 with an average of 0.71. From the results of this study we can get a conclusion that the genetic differences among the wild populations of P. subaequalis in Dalonggou of Yixing, Jiangsu were large and rich in diversity. The aim of this study is to reveal the genetic diversity of wild population of P. subaequalis from molecular level and provide a theoretical basis for the protection of this rare and endangered plant.

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Zhang, Yang, Pedro N. Carvalho, Tao Lv, Carlos Arias, Hans Brix, and Zhanghe Chen. "Microbial density and diversity in constructed wetland systems and the relation to pollutant removal efficiency." Water Science and Technology 73, no. 3 (October 21, 2015): 679–86. http://dx.doi.org/10.2166/wst.2015.542.

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Microbes are believed to be at the core of the wastewater treatment processes in constructed wetlands (CWs). The aim of this study was to assess the microbial biomass carbon (MBC) and Shannon's diversity index (SDI) in the substrate of CWs planted with Phragmites australis, Hymenocallis littoralis, Canna indica and Cyperus flabelliformis, and to relate MBC and SDI to the pollutant removal in the systems. Significant higher MBC was observed in CWs with H. littoralis and C. indica than in CWs with P. australis, and the MBC differed with season and substrate depth. The microbial community in the wetlands included four phyla: Cyanobacteria, Proteobacteria, Chloroflexi, and Acidobacteria, with a more diverse community structure in wetlands with C. flabelliformis. The MBC in the substrate and the SDI of the 15–20 cm depth correlated with the removal of biochemical oxygen demand, NH4-N and NO3-N. Our results indicate that substrate SDI and MBC can both be regarded as bioindicators of the pollutant removal ability in CWs.

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Ge, Bao-Ming, Yi-Xin Bao, Hong-Yi Cheng, Dai-Zhen Zhang, and Zhi-Yuan Hu. "Influence of Spartina alterniflora invasion stages on macrobenthic communities on a tidal flat in Wenzhou Bay, China." Brazilian Journal of Oceanography 60, no. 3 (September 2012): 441–48. http://dx.doi.org/10.1590/s1679-87592012000300014.

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Many coastal habitats in eastern China are being substantially altered by the invasion of Spartina alterniflora. The species richness, density, Margalef's diversity index (R) and Shannon's diversity index (H') of macrobenthic communities on a tidal flat in Wenzhou Bay, China, were analyzed with the factors of invasion stage and season, in 2007. A significant effect of invasion stage, season, and the interaction between them on communities was detected. The macrobenthic community was more complex in the patch of initial S. alterniflora invasion than in the patches of some other invasion stages. Macrobenthic communities were classified by cluster and ordination in accordance with the habitat character of the S. alterniflora invasion stage. Our research demonstrated that the S. alterniflora invasion stage affected the macrobenthic communities significantly. The results indicated that biodiversity increased in the initial stage of invasion (invasion age 1-2 years) and then decreased in the stage of invasion underway (invasion age 3-4 years) and in the stage of invasion completed (invasion age 5-6 years); this phenomenon was related to the change in the S. alterniflora canopy which accompanied the invasion stages.

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Sühs, Rafael Barbizan, and Jean Carlos Budke. "Spatial distribution, association patterns and richness of tree species in a seasonal forest from the Serra Geral formation, southern Brazil." Acta Botanica Brasilica 25, no. 3 (September 2011): 605–17. http://dx.doi.org/10.1590/s0102-33062011000300014.

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This study aimed to determine the spatial distribution of the most abundant tree species, to look for relationships that may be responsible for their distribution and to compare the expected richness along the Serra Geral formation in the state of Rio Grande do Sul , Brazil. An one-hectare plot was divided in 100 contiguous 10 x 10 m sampling units and all individuals with at least 4.8 cm diameter at breast high were measured and identified. Each sampling unit received a description of the spatial position through metric coordinates (x,y) in order to quantify the spatial pattern. Later, an association index among species was applied. The observed richness was rarefied and compared to other surveys located on the slopes of Serra Geral in Rio Grande do Sul. We surveyed 1,063 individuals belonging to 69 species and 33 families, and the Shannon's diversity index showed a diversity of 3.35 nats (Pielou's species evenness - J' = 0.79). Most species showed an aggregated distribution. Both association and dissociation patterns occurred among species leading to distinct forest patches. The rarefaction results showed a decrease of Atlantic species, which were replaced by typical seasonal forest species, when analyzing floristic contingents towards the west.

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Carrasco, Basilio, Marcelo Garcés, Pamela Rojas, Guillermo Saud, Raúl Herrera, Jorge B. Retamales, and Peter D. S. Caligari. "The Chilean Strawberry [Fragaria chiloensis (L.) Duch.]: Genetic Diversity and Structure." Journal of the American Society for Horticultural Science 132, no. 4 (July 2007): 501–6. http://dx.doi.org/10.21273/jashs.132.4.501.

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The chilean strawberry displays high fruit quality and tolerance to abiotic and biotic factors. Additionally, this species has a rich cultural history going back for at least several thousand years in association with aboriginal people activities and continues at a reduced level today. After its introduction to Europe during the 18th century, it formed an interspecific hybrid to become the maternal species of the commercial strawberry, Fragaria ×ananassa Duch. The objectives of the current investigation were to determine the level and patterns of partitioning of intersimple sequence repeat (ISSR) diversity. ISSR markers were used to assess the genetic diversity in 216 accessions of F. chiloensis, which represented the two botanical forms present in Chile [F. chiloensis ssp. chiloensis f. chiloensis and F. chiloensis ssp. chiloensis f. patagonica (L.) Duch.]. Our results showed high genetic diversity at the species level [polymorphic ISSR loci (P) = 89.6%, gene diversity (h) = 0.24 ± 0.17, Shannon's index (S) = 0.37 ± 0.24] and a lower genetic diversity in f. chiloensis than f. patagonica. The analysis of molecular variance (AMOVA) showed a moderate genetic differentiation among accessions (φst = 14.9%). No geographic patterns for ISSR diversity were observed. AMOVA, structure, and discriminant analysis indicated that accessions tend to group by botanical form. The impact of domestication on the genetic structure of chilean strawberry and its application to breeding and conservation are discussed.

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Saikia, Sandhani, Pratap Jyoti Handique, and Mahendra K. Modi. "Population structure and genetic diversity analysis in Sali (Oryza sativa) rice germplasm of Assam using microsatellite markers." Oryza-An International Journal on Rice 58, no. 2 (June 30, 2021): 279–86. http://dx.doi.org/10.35709/ory.2021.58.2.4.

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Genetic diversity is the source of novel allelic combinations that can be efficiently utilized in any crop improvement program. To facilitate future crop improvement programs in rice, a study was designed to identify the underlying genetic variations in the Sali rice germplasms of Assam using SSR markers. The 129 SSR markers that were used in the study amplified a total of 765 fragments with an average of 5.93 alleles per locus. The Shannon's Information Index was found to be in the range from 0.533 to 1.786. The Polymorphism Information Content (PIC) fell into the range from 0.304 to 0.691 with a mean value of 0.55. The overall FST value was found to be 0.519 that indicated the presence of genetic differentiation amongst the genotypes used in the study. The Sali population was divided into two clusters. The information obtained from the present study will facilitate the genetic improvement of Sali rice cultivars.

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Barry, M. B., A. Diagne, M. J. Sogbossi, J. L. Pham, S. Diawara, and N. Ahmadi. "Recent changes in varietal diversity of rice in Guinea." Plant Genetic Resources 7, no. 1 (April 2009): 63–71. http://dx.doi.org/10.1017/s1479262108060930.

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Rice varietal diversity was assessed in Guinea on the basis of surveys of 1679 farms located in 79 villages of the four natural regions of the country. The descriptors used were the number of known varieties, the number of cultivated varieties and Shannon's diversity and evenness index. On the basis of their use rates, varieties were classified as major or minor types at the village scale and as regionally and/or nationally eminent varieties at these scales. Varietal diversity was high, especially in forest Guinea and lower Guinea. Diversity pattern was typical of the subsistence farming system. The high share of local variety reflected the predominance of low management and low input cropping systems. The presence of improved varieties confirms farmers' openness to innovation and to the government policy of promoting improved varieties. Regional diversity reflected the agro-ecological diversity and specificities of each region, the history and the extent of rice-growing systems, and the importance of rice in the local diet. Recent dissemination of NERICA varieties has not caused any reduction of pre-existing varieties. The short-duration NERICA are mainly used as a complement to the long-duration traditional varieties and thus enhance varietal diversity. Risks of diversity erosion seem limited in the current setting of farming system and diversity structure. However, at the village level, the diversity pattern is fragile as the proportion of farmers who used each variety of the village is low and heterogeneous. A continuous monitoring of the dynamics of rice varietal diversity in Guinea is needed.

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Grijalbo, Lucía, Carlos Garbisu, Iker Martín, Javier Etxebarria, F. Javier Gutierrez-Mañero, and Jose Antonio Lucas Garcia. "Functional diversity and dynamics of bacterial communities in a membrane bioreactor for the treatment of metal-working fluid wastewater." Journal of Water and Health 13, no. 4 (June 15, 2015): 1006–19. http://dx.doi.org/10.2166/wh.2015.079.

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An extensive microbiological study has been carried out in a membrane bioreactor fed with activated sludge and metal-working fluids. Functional diversity and dynamics of bacterial communities were studied with different approaches. Functional diversity of culturable bacterial communities was studied with different Biolog™ plates. Structure and dynamics of bacterial communities were studied in culturable and in non-culturable fractions using a 16S rRNA analysis. Among the culturable bacteria, Alphaproteobacteria and Gammaproteobacteria were the predominant classes. However, changes in microbial community structure were detected over time. Culture-independent analysis showed that Betaproteobacteria was the most frequently detected class in the membrane bioreactor (MBR) community with Zoogloea and Acidovorax as dominant genera. Also, among non-culturable bacteria, a process of succession was observed. Longitudinal structural shifts observed were more marked for non-culturable than for culturable bacteria, pointing towards an important role in the MBR performance. Microbial community metabolic abilities assessed with Biolog™ Gram negative, Gram positive and anaerobic plates also showed differences over time for Shannon's diversity index, kinetics of average well colour development, and the intensely used substrates by bacterial community in each plate.

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Goulart, Maíra Figueiredo, Sérvio Pontes Ribeiro, and Maria Bernadete Lovato. "Genetic, morphological and spatial characterization of two populations of Mabea fistulifera Mart. (Euphorbiaceae), in different successional stages." Brazilian Archives of Biology and Technology 48, no. 2 (March 2005): 275–84. http://dx.doi.org/10.1590/s1516-89132005000200015.

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Two populations of Mabea fistulifera (Euphorbiaceae) located at Rio Doce State Park (Minas Gerais, Brazil) in places characterized as in different successional stages, were investigated through genetic and ecological traits. Twenty randomly chosen individuals from each population had its genetic data assessed by 43 RAPD markers and were also evaluated through five morphologic traits and its spatial distribution. Both Shannon's index and AMOVA reveled that most of the genetic variation was found between individuals within populations and about 9% of variation was located between populations. Moreover, populations differed genetically, but presented similar values of genetic diversity. Morphologic data showed differences between populations. Significant correlations among matrix of genetic, geographic and morphologic distances were obtained considering both populations, and spatially closer individuals were more similar genetically, characterizing genetic substructured populations.

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Volkmer-Ribeiro, C., D. L. Guadagnin, R. De Rosa-Barbosa, M. M. Silva, S. Drügg-Hahn, V. L. Lopes-Pitoni, H. A. de O. Gastal, M. P. Barros, and L. V. Demaman. "A Polyethylenetherephthalate (PET) device for sampling freshwater benthic macroinvertebrates." Brazilian Journal of Biology 64, no. 3a (August 2004): 531–41. http://dx.doi.org/10.1590/s1519-69842004000300016.

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A new device to sample freshwater benthic macroinvertebrates was used in a low and sandy stretch of a Brazilian sub-tropical river (the River Caí, Triunfo, RS) and in one of its small tributaries, Bom Jardim brook (Arroio Bom Jardim). In this study, the effectiveness of this device, a PET sampler, was tested at different sites in the river and the brook throughout the four seasons between 2001-2002. Comparisons were made by PCA and ANOVA, both employing a bootstrap procedure based on similarity matrices. The PET sampler proved to be a reliable tool for detection of seasonal and spatial differences in richness, total abundance of organisms, and Shannon's diversity index in both river and brook and is therefore recommended for use in the monitoring of macroinvertebrate communities in this system.

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Anand, Kumar Kamal, Ravi Kumar Srivastava, and Lal Babu Chaudhary. "Analysis of Genetic Diversity in Astragalus rhizanthus Benth. ssp. rhizanthus var. rhizanthus (Fabaceae) Using Molecular Markers from India." Journal of Botany 2010 (May 19, 2010): 1–9. http://dx.doi.org/10.1155/2010/701975.

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Astragalus rhizanthus with three infraspecific taxa (i.e., A. rhizanthus ssp. rhizanthus var. rhizanthus, A. rhizanthus ssp. rhizanthus var. pindreensis, and A. rhizanthus ssp. candolleanus) is widely scattered in the Himalaya from Jammu and Kashmir to Uttarakhand provinces in India. Among them, A. rhizanthus ssp. rhizanthus var. rhizanthus exhibits enormous morphological diversity throughout its range of distribution. An assessment of genetic diversity studies was undertaken to understand the level and pattern of diversity, using Inter simple sequence repeats (ISSR), Random amplified polymorphic DNA (RAPD) and Directed amplification of minisatellite DNA (DAMD) profiles. Fifteen ISSR, 18 RAPD and 6 DAMD primers were used to unravel the diversity among 20 genotypes collected from the known localities in the Indian Himalaya. A total of 242 bands from ISSR, 352 from RAPD and 142 from DAMD were obtained with an average of 92.23% polymorphism in the species. Pair-wise genetic similarity for the cumulative data was determined using Jaccard's similarity coefficient which varied from 0.19 to 0.84. A combined UPGMA dendrogram was generated which revealed that different genotypes exhibited their affinity according to their geographical distribution. Tree topology suggests the existence of two distinct groups of the genotypes. Gene diversity (H) and Shannon's information index (I) were estimated and these values were found higher in the genotypes collected from Jammu and Kashmir than Himachal Pradesh.

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Hilwan, Iwan, and Meida Rosani. "Respon Pertumbuhan Tanaman Reklamasi PT Newmont Nusa Tenggara terhadap Penggunaan Mulsa Organik Kardus." Journal of Tropical Silviculture 11, no. 2 (August 21, 2020): 109–17. http://dx.doi.org/10.29244/j-siltrop.11.2.109-117.

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Plant growth determined factors such as environmental manipulation of seeds, including maintenance and pest disease prevention integrated. Intensive maintenance needs to be done especially when the plant is still young-old. Use organic mulch cardboard including part of plant maintenance to suppress weed competition with staple crops at a young age. In addition the use of mulch, organic boxes are expected to give positive influence against the growth of staple crops and chemical properties as well as land reclamation in soil biology. The results showed that organic mulching cardboard gives positive influence against the reclamation plant growth based on parameters of high and in diameter. The development of plants under around staple crops can be suppressed. Chemical properties of the soil showed improvement in some elements of the chemistry of the soil with organic mulch using cardboard. The diversity of types of makrofauna the soil around the plants with mulch treatments staple cardboard categories include being with Shannon's Diversity index value-Wiener of 1.57 while in treatment control categories include low value of 1.48. Keywords: cardboard mulch, plant growth, reclamation, weed

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Cieślak, Elżbieta, and Zbigniew Szeląg. "Genetic diversity of Galium cracoviense, G. oelandicum and G. sudeticum (Rubiaceae)." Acta Societatis Botanicorum Poloniae 79, no. 4 (2011): 269–75. http://dx.doi.org/10.5586/asbp.2010.034.

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Galium sect. Leptogalium Lange in NE Europe is represented by few, local endemic species which occur in the area covered by the continental ice sheet in the Pleistocene period. They are: G. cracoviense Ehrend. in S Poland, G. oelandicum (Sterner & Hyl.) Ehrend. in SE Sweden and G. sudeticum Tausch in SW Poland and N Czech Republic. 55 individuals from five populations of these species were analysed using AFLP markers. A total of 193 AFLP bands were detected using three combinations of primers; out of them 159 proved polymorphic (82.4%). The lowest values of Shannon's index and Nei's gene diversity were noted for G. oelandicum and the highest ones for G. sudeticum. The results indicate a relatively high level of genetic variability in each of endemic species in spite of that the studied species occupy very small areas and are represented by a low number of populations. We conclude that additional, demographic and genetic studies are necessary to monitor potential decrease of populations' size resulting mainly from the mechanical destruction of plants and their habitats caused by intense tourism or other human activities (as agriculture, e.g. grazing).

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Journal articles on the topic 'Shannon's Diversity Index'

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