scholarly journals Species presence frequency and diversity in different patch types along an altitudinal gradient:Larix chinensisBeissn in Qinling Mountains (China)

PeerJ ◽  
2016 ◽  
Vol 4 ◽  
pp. e1803 ◽  
Author(s):  
Minyi Huang ◽  
Renyan Duan ◽  
Shixiong Wang ◽  
Zhigao Wang ◽  
Weiyi Fan
Keyword(s):  
Functional Groups ◽  
Diversity Index ◽  
Dispersal Limitation ◽  
Diversity Indices ◽  
Coniferous Forests ◽  
Qinling Mountains ◽  
Larix Chinensis ◽  
Species Groups ◽  
Patch Scale ◽  
Adjacent Patch

Forest communities are mosaic systems composed of patches classified into four different developmental patch types: gap patch (G), building patch (B), mature patch (M) and degenerate patch (D). To study the mechanisms maintaining diversity in subalpine coniferous forests, species presence frequency and diversity in the four distinct patch types (G, B, M and D) ofLarix chinensisconifer forests at three altitudinal gradients in the Qinling Mountains were analyzed. Our results were as follows: (1) Different species (or functional groups) had distinct presence frequencie s in the four different patch types along the altitudinal gradient; (2) Some species or functional groups (species groups sharing similar traits and response to environment) only occurred in some specific patches. For seed dispersal, species using wind mainly occurred in G and D, while species using small animals mainly occurred in B and M; (3) Species composition of adjacent patch types was more similar than non-adjacent patch types, based on the lowerβdiversity index of the former; (4) The maximum numbers of species and two diversity indices (D′ andH′) were found in the middle altitudes. Various gap-forming processes and dispersal limitation may be the two major mechanisms determining species diversity inLarix chinensisconiferous forests at the patch scale.

scholarly journals Species presence frequency and diversity in different patch types along an altitudinal gradient: Larix chinensis Beissn in Qinling Mountains (China)

2016 ◽  
Author(s):  
Minyi Huang ◽  
Renyan Duan ◽  
Shixiong Wang ◽  
Zhigao Wang ◽  
Weiyi Fan
Keyword(s):  
Functional Groups ◽  
Altitudinal Gradient ◽  
Diversity Index ◽  
Dispersal Limitation ◽  
Diversity Indices ◽  
Coniferous Forests ◽  
Qinling Mountains ◽  
Larix Chinensis ◽  
Species Groups ◽  
Adjacent Patch

Forest communities are mosaic systems composed of patches classified into four different developmental patch types: gap patch (G), building patch (B), mature patch (M) and degenerate patch (D). To study the mechanisms maintaining diversity in subalpine coniferous forests, species presence frequency and diversity in the four distinct patch types (G, B, M and D) of Larix chinensis conifer forests at three altitudinal gradients in the Qinling Mountains were analyzed. Our results were as follows: (1) Different species (or functional groups) had distinct presence frequencie s in the four different patch types along the altitudinal gradient. (2) Some species or functional groups (species groups sharing similar traits and response to environment) only occurred in some specific patches. For seed dispersal, species using wind mainly occurred in G and D, while species using small animals mainly occurred in B and M. (3) Species composition of adjacent patch types was more similar than non-adjacent patch types, based on the lower β diversity index of the former. (4) The maximum numbers of species and two diversity indices (D′ and H′) were found in the middle altitudes. Various gap-forming processes and dispersal limitation may be the two major mechanisms determining species diversity in Larix chinensis coniferous forests at the patch scale.

scholarly journals Species presence frequency and diversity in different patch types along an altitudinal gradient: Larix chinensis Beissn in Qinling Mountains (China)

2016 ◽  
Author(s):  
Minyi Huang ◽  
Renyan Duan ◽  
Shixiong Wang ◽  
Zhigao Wang ◽  
Weiyi Fan
Keyword(s):  
Functional Groups ◽  
Altitudinal Gradient ◽  
Diversity Index ◽  
Dispersal Limitation ◽  
Diversity Indices ◽  
Coniferous Forests ◽  
Qinling Mountains ◽  
Larix Chinensis ◽  
Species Groups ◽  
Adjacent Patch

Forest communities are mosaic systems composed of patches classified into four different developmental patch types: gap patch (G), building patch (B), mature patch (M) and degenerate patch (D). To study the mechanisms maintaining diversity in subalpine coniferous forests, species presence frequency and diversity in the four distinct patch types (G, B, M and D) of Larix chinensis conifer forests at three altitudinal gradients in the Qinling Mountains were analyzed. Our results were as follows: (1) Different species (or functional groups) had distinct presence frequencie s in the four different patch types along the altitudinal gradient. (2) Some species or functional groups (species groups sharing similar traits and response to environment) only occurred in some specific patches. For seed dispersal, species using wind mainly occurred in G and D, while species using small animals mainly occurred in B and M. (3) Species composition of adjacent patch types was more similar than non-adjacent patch types, based on the lower β diversity index of the former. (4) The maximum numbers of species and two diversity indices (D′ and H′) were found in the middle altitudes. Various gap-forming processes and dispersal limitation may be the two major mechanisms determining species diversity in Larix chinensis coniferous forests at the patch scale.

scholarly journals On a Variational Definition for the Jensen-Shannon Symmetrization of Distances Based on the Information Radius

Entropy ◽  
2021 ◽  
Vol 23 (4) ◽  
pp. 464
Author(s):  
Frank Nielsen
Keyword(s):  
Diversity Index ◽  
Diversity Indices ◽  
Shannon Diversity Index ◽  
Probability Measures ◽  
Variational Optimization ◽  
Shannon Diversity ◽  
Concept Of Information ◽  
Jensen Shannon Divergence

We generalize the Jensen-Shannon divergence and the Jensen-Shannon diversity index by considering a variational definition with respect to a generic mean, thereby extending the notion of Sibson’s information radius. The variational definition applies to any arbitrary distance and yields a new way to define a Jensen-Shannon symmetrization of distances. When the variational optimization is further constrained to belong to prescribed families of probability measures, we get relative Jensen-Shannon divergences and their equivalent Jensen-Shannon symmetrizations of distances that generalize the concept of information projections. Finally, we touch upon applications of these variational Jensen-Shannon divergences and diversity indices to clustering and quantization tasks of probability measures, including statistical mixtures.

scholarly journals Distance Effects on Diversity and Abundance of the Flower Visitors of Ocimum kilimandscharicum in the Kakamega Forest Ecosystem

2018 ◽  
Vol 2018 ◽  
pp. 1-7 ◽  
Author(s):  
Hellen K. Mandela ◽  
Mugatsia H. Tsingalia ◽  
Mary Gikungu ◽  
Wilbur M. Lwande
Keyword(s):  
Species Diversity ◽  
Diversity Index ◽  
Land Use Changes ◽  
Species Abundance ◽  
Diversity Indices ◽  
Forest Edge ◽  
Flower Visitors ◽  
Kakamega Forest ◽  
Species Invasions ◽  
Wiener Diversity Index

Pollination is an important ecosystem service in the maintenance of biodiversity and most importantly in food production. Pollination is on the decline due to habitat loss, exotic species invasions, pollution, overharvesting, and land use changes. This study analyzed the abundance and diversity of flower visitors’ of Ocimum kilimandscharicum in Kakamega forest with increasing distance from the forest edge. Data were collected through direct observation and sweep netting. Six study sites were identified along two transects each 2.5 km long and labeled A to F. Distance in metres from the forest edge to each site was A=221, B=72, C=83, D=198, E=113, and F=50. Sampling was done from 7:30 am to 4:00 pm, three days in a week for five months consecutively. Diversity indices of different flower visitors were calculated using the Shannon-Wiener diversity index. One-way analysis of variance was used to compare differences between sites and a two-sample t-test was used to identify mean significant differences in species diversity between the closest and the furthest sites. A total of 645 individuals belonging to 35 species were captured from 4 families. The highest diversity was at site F (H’= 2.38) which was closest to the forest edge and the lowest diversity was from site A (H’=1.44) which was furthest from the forest edge. Distance from the forest edge significantly influenced species diversity (F(3, 20)=14.67, p=0.024). Distance from the forest edge also significantly influenced species abundance between the furthest sites A, D, and E and the nearest sites F, B, and C to the forest edge (t=4.177; p=0.0312) and species richness (t=3.2893; p=0.0187). This study clearly demonstrates that Ocimum kilimandscharicum flower visitors play essential roles in pollination and their higher number of visits translates into higher numbers of seeds set. Many of these pollinators are associated with the forest and hence the need to conserve the Kakamega forest as a source pool for pollinators.

scholarly journals Phytoplankton assemblages in Lake Orta: has functional structure recovered in one of the largest acidic lakes in the world?

2016 ◽  
Vol 75 (s2) ◽  
Author(s):  
Giuseppe Morabito
Keyword(s):  
Functional Groups ◽  
Diversity Indices ◽  
Taxonomic Composition ◽  
Ecological Niches ◽  
Phytoplankton Species ◽  
Phytoplankton Assemblages ◽  
Lake Maggiore ◽  
Acidic Lakes ◽  
Physical Features ◽  
She Analysis

Lake Orta (Northern Italy) became one of the world’s largest acidic lakes, following industrial pollution, beginning in the late 1920s. Prior to pollution, Lake Orta supported a rich and diversified phytoplankton community dominated by diatoms, cyanobacteria and dinoflagellates. Their taxonomic composition was comparable to that of the nearby Lake Maggiore, which provides a useful reference comparison. After pollution, Lake Orta was so acidic and contaminated with trace metals that only a few tolerant phytoplankton species persisted, supplemented by sudden and short living outbursts of occasional colonists. The lake was limed in 1989-1990. This has permitted the gradual recovery of its chemistry and biology, and many phytoplankton species that inhabit Lake Maggiore are now re-appearing in Lake Orta. I tested the two hypotheses that Lakes Orta and Maggiore would now have a similar phytoplankton taxonomic assemblages, and similar diversity of functional groups given their similar morphometry, physical features and trophic states. The two hypotheses were tested by comparing the phytoplankton assemblages of lakes Maggiore and Orta for the first 10 years after liming, i.e. 1990 to 2001. Phytoplankton was classified according the Reynolds' Morpho Functional Groups and five diversity indices were calculated (<em>S</em>, number of units; <em>H</em>, Shannon-Wiener; <em>E</em>, evenness; <em>D</em>, dominance; <em>J</em>, equitability). SHE analysis (an analysis of diversity changes based on the relationship among species richness (S), H Index (H) and evenness (E)) was also carried out, in order to compare the long term trend of both functional groups and taxa biodiversity. Both taxonomic and the functional composition differed in the two lakes, likely because chemical quality have played a role in <em>taxa</em>selection. Moreover, it was quite clear that, during the first post-liming decade, Lake Orta’s phytoplankton was characterized by low diversity and evenness and by marked year-to-year fluctuations. However, SHE analysis showed that the colonization rate was higher in Lake Orta than in Lake Maggiore, and that the environmental modifications caused by the liming were opening new ecological niches, allowing some colonists to thrive in the changing, albeit still unusual chemical environment of the lake.<p> </p>

scholarly journals Abundance of ants (Hymenoptera: Formicidae) and the functional groups in two different habitats

2020 ◽  
Vol 21 (5) ◽  
Author(s):  
Ananto Triyogo ◽  
Budiadi ◽  
Siti Muslimah Widyastuti ◽  
Sena Adi Subrata ◽  
Suwito Susetyo Budi
Keyword(s):  
Functional Groups ◽  
Native Species ◽  
Diversity Index ◽  
Species Abundance ◽  
Land Development ◽  
Invasive Ants ◽  
Ant Communities ◽  
Anoplolepis Gracilipes ◽  
Research Education ◽  
June July

Abstract. Triyogo A, Budiadi, Widyastuti SM, Subrata SA, Budi SS. 2020. Abundance of ants (Hymenoptera: Formicidae) and the functional groups in two different habitats. Biodiversitas 21: 2079-2087. Land development often affects the quantity and diversity of ants (Hymenoptera: Formicidae). The aim of this study, therefore, was to determine and compare the ant species abundance and the functional groups between two different habitats, representing land development, including pioneer and agroforestry. This research involved a survey of the ants at the Forest Research Education (FRE) of Wanagama I Yogyakarta, and data were accumulated over a period of five months (April, May, June, July, and August). In addition, pit-fall trap and direct collection methods were used, involving the placement of 54 pit-fall traps at two habitats, and the ant specimens were retrieved after a two day period. The results show the total individual abundance of 2,310 and 2,067, on agroforestry and pioneer, respectively. Furthermore, the species richness and diversity index was higher in agroforestry (7; 2.01), compared with pioneer (6; 1.49), where the three dominant species include, Anoplolepis gracilipes, Solenopsis sp., Odontoponera denticulata; and Anoplolepis gracilipes, Odontoponera denticulata, Camponotus sp., respectively. Conversely, the highest amount of invasive ants (Solenopsis sp.) was observed in agroforestry, which negatively impacted on the presence of native species (Odontoponera denticulata). In addition, PCA analysis showed the development of three ant groups on each habitat, hence agroforestry made more real differences in the aspect of species abundance, and none in terms of richness. Therefore, notable differences were observed in the ant communities between both habitats, and agroforestry was indicated as a disturbed area, based on the increment in tramp and invasive ants, alongside low abundance of native and functional groups.

scholarly journals Effect of Wastewater Discharge From Coffee Processing Plant on River Water Quality, Sidama Region, South Ethiopia

2021 ◽  
Vol 15 ◽  
pp. 117863022110610
Author(s):  
Wubalem Genanaw ◽  
Girum Gebremeskel Kanno ◽  
Dawit Derese ◽  
Mekonnen Birhanie Aregu
Keyword(s):  
Water Quality ◽  
River Water ◽  
Physicochemical Parameters ◽  
Diversity Index ◽  
Sampling Technique ◽  
Diversity Indices ◽  
River Water Quality ◽  
Processing Plant ◽  
Processing Plants ◽  
Raw Wastewater

In Ethiopia, most of the coffee processing plants are generating large amounts of wastewater with high pollutant concentrations and discharge directly into the water bodies untreated or partially treated. The main objective of this study was to assess the effects of coffee wastewater discharged to river water quality using physicochemical parameters and macro-invertebrate indices. This study was conducted from November to the end of December 2019. Ten wastewater and river water samples were taken from coffee the processing plant and river. The macro-invertebrate samples were collected by kick sampling technique using a standard hand net. Shannon and Simpson diversity indices were examined at 3 sampling stations. The Pielou evenness index was also determined. It was found that except for TDS all the parameters of the raw wastewater and river water did not comply with the international discharge limit. The mean concentration of Faro coffee processing plant wastewater were BOD5 (2409.6 ± 173.1 mg/L), COD (4302 ± 437 mg/L), TSS (2824.6 ± 428.4 mg/L), TDS (3226 ± 623.6 mg/L), and TS (4183.3 ± 432.9 mg/L). Whereas from Bokaso coffee processing plant were BOD5 (3770 ± 604.4 mg/L), COD (4082.6 ± 921.9 mg/L), TSS (2766 ± 501.7 mg/L), TDS (3017 ± 747.6 mg/L), and TS (3874 ± 471.1 mg/L). A total of 392 macroinvertebrates belonging to 24 families and 7 orders were collected. The benthos assemblage communities in this river were 40, 56, and 296 at downstream 1, downstream 2, and upstream respectively. The value of the Simpson diversity index varies from 0.4 to 0.75. In the same manner, the value of the Shannon diversity index also varied from 0.5 to 1.36. Most of the physicochemical parameters of the raw wastewater were beyond the national and international discharge limits. The quality of Orsha river water downstream was more adversely affected compared to upstream.

scholarly journals Diversitas Tumbuhan Liar Pada Lahan Jagung (Zea mays L.) di Desa Bungbungan Kecamatan Bluto Kabupaten Sumenep

2020 ◽  
Vol 6 (1) ◽  
pp. 54-60
Author(s):  
Khoiratul Hasanah ◽  
Ari Hayati ◽  
Hasan Zayadi
Keyword(s):  
Zea Mays ◽  
Agricultural Land ◽  
Zea Mays L ◽  
Crop Yields ◽  
Diversity Index ◽  
Diversity Indices ◽  
Wild Plants ◽  
Wild Plant ◽  
Cultivated Plants ◽  
Number Of Individuals

Wild plants are plants whose presence on agricultural land can reduce crop yields. Losses due to wild plants to cultivated plants vary depending on the type of plant cultivated, climate, species of wild plants and technical cultivation applied. This study aims to determine the diversity of wild plants in the land of maize (Zea mays L.) in Bung-bungan Village Bluto District Sumenep Regency. This method uses a descriptive exploratory method, for each wild plant found in ± 3600 m2 of corn land. Sampling of wild plants using a 4x4 m plot method. The measured data includes the number of species and the number of individuals calculating important values ​​and diversity indices. The results of the study showed that the Shannon-Wienner Diversity Index analysis of the highest value in maize plants in plantations was found in land II, which was 2.678 indicating moderate diversity, categorized as moderate because there were not too many wild plants on maize.  Keywords: Corn, diversity, wild plants,  ABSTRAK Tumbuhan liar merupakan tumbuhan yang kehadirannya pada lahan pertanian dapat menurunkan hasil tanaman. Kerugian akibat tumbuhan  liar terhadap tanaman budidaya beragam bergantung dari jenis tanaman yang diusahakan, iklim, jenis tumbuhan  liar dan teknis budidaya yang diterapkan. Penelitian ini bertujuan untuk mengetahui diversitas tumbuhan liar di lahan jagung (Zea mays L.) di Desa Bung-bungan Kecamatan Bluto Kabupaten Sumenep. Metode ini menggunakan metode deskriptif eksploratif, terhadap setiap tumbuhan liar yang ditemukan pada lahan jagung seluas ±3600 m2. Pengambilan sampel tumbuhan liar menggunakan metode plot berukuran 4x4 m. Data yang diukur meliputi jumlah spesies dan jumlah individu menghitung nilai penting dan indeks diversitas. Hasil penelitian menunjukkan analisis Indeks Keanekaragaman Shannon-Wienner tumbuhan liar nilai tertinggi pada tanaman jagung di lkebun terdapat pada lahan II yaitu 2,678 menunjukkan keanekaragaman sedang, di kategorikan sedang karena jenis tanaman liar yang ada pada lahan jagung tidak terlalu banyak. Kata kunci: Jagung, Diversitas, Tanaman liar

Transition management for organic agriculture under citrus cultivation favors fungal diversity in soil

2018 ◽  
Vol 35 (2) ◽  
pp. 120-127
Author(s):  
Juliana Cristina Scotton ◽  
Sérgio Kenji Homma ◽  
Wesley Luiz Fialho Costa ◽  
Diego Fontebasso Pelizari Pinto ◽  
José Silvio Govone ◽  
...  
Keyword(s):  
Organic Agriculture ◽  
Management System ◽  
Fungal Diversity ◽  
Diversity Index ◽  
Principal Component ◽  
Diversity Indices ◽  
Transition Management ◽  
Farming Practices ◽  
Soil Fungal Community ◽  
Innovative Solution

AbstractThe present international scenario recognizes organic agriculture as an innovative solution to reduce agrochemicals and practices that degrade the agroecosystem. Yet, the shift from an already well-established agricultural model to a relatively new one is a challenging task and requires further scientific support. This work investigated the influence of transitional management – TM (from conventional to organic agriculture) on the soil fungal community under citrus, in dry and rainy periods. From 2012 to 2015 on, an area in Mogi Guaçú, SP, Brazil was selected, and two treatments were installed: a conventional management (CM) system based on farming practices with agrochemicals and fertilizers use, and another, transition management (TM) based on a 25% reduction per year of the chemical substances used in CM, with soil conditioner bokashi introduced. The performance of the transition system was evaluated in the context of soil fertility and diversity index of fungal taxa, by plate culture isolation, through the richness of Margalef (Dmg), diversity of Shannon (H′) and reverse Simpson (D). Differences in the occurrence and frequency of Paecilomyces, greater under CM and Penicillium, greater under TM, highlighted the influence of the management system employed. Richness and diversity indices were higher under TM. Principal component analysis revealed that 49.9% of the differences in fungal diversity was due to the management system. Only 16.5% was a result of the season of sampling. Four years of reduction/replacement of chemical practices in TM was sufficient to modify and favor some soil fungal taxa and consequently their activity. This research brings promising results to organic agriculture initiatives with relevant results for a tropical climate area.

scholarly journals Tree species diversity in the forest of Renikhayong para village in Bandarban, Bangladesh: a case study

2020 ◽  
Vol 5 (2) ◽  
pp. 115-126 ◽  
Author(s):  
M Jannat ◽  
M Kamruzzaman ◽  
MA Hossain ◽  
MK Hossain
Keyword(s):  
Species Diversity ◽  
Tree Species ◽  
Diversity Index ◽  
Sustainable Use ◽  
Tree Height ◽  
Diversity Indices ◽  
Tree Species Diversity ◽  
Height Range ◽  
Hill District ◽  
Number Of Individuals

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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