scholarly journals Myxomycetes of the Caramoan Islands and an update on the species found in the Bicol Peninsula, Philippines

2021 ◽  
Vol 14 (1) ◽  

The main objective of this study was to characterize the assemblages of myxomycetes on isolated Philippine islands through a correlational study using geographical and ecological distance in the Caramoan Islands, including an updated checklist of the myxomycetes of the Bicol Peninsula. Four islands of varying sizes and distances from each other, but all within relatively close proximity to the mainland of the Bicol Peninsula, were surveyed. A combination of traditional and more contemporary ecological tools was used to analyze diversity indices among and between the islands. Among the four islands, Matukad Island recorded the highest species richness (46.8) and taxonomic diversity index (2.6), while ranking next to Lahos island in terms of species diversity (7.9). Pairwise comparisons using community similarity indices and clustering analysis consistently showed that Lahos and Matukad are the most similar to each other, while also being closer to one another but situated farthest from the mainland. On the other hand, the two smallest islands, which were also closest to each other and to the mainland, grouped together using clustering analysis but recorded the lowest pairwise percentage similarity value. The ecological patterns in this study appear to follow the unified neutral theory of biodiversity and biogeography more than the insular biogeography theory. In addition, this study added 16 new morphospecies to the list of myxomycetes known from the Bicol Peninsula, which brings the total to 73, including one new record for the country [Lamproderma arcyrioides (Sommerf.) Rostaf.] KEYWORDS: slime molds, insular, biodiversity, paleotropics, unified netural theory

2018 ◽  
Author(s):  
Keiichi Fukaya ◽  
Buntarou Kusumoto ◽  
Takayuki Shiono ◽  
Junichi Fujinuma ◽  
Yasuhiro Kubota

AbstractEvolutionary processes underpin the biodiversity on the planet. Theories advocate that the form of the species abundance distribution (SAD), presented by the number of individuals for each species within an ecological community, is intimately linked to speciation modes such as point mutation and random fission. This prediction has rarely been, however, verified empirically; the fact that species abundance data can be obtained only from local communities critically limits our ability to infer the role of macroevolution in shaping ecological patterns. Here, we developed a novel statistical model to estimate macroscale SADs, the hidden macroecological property, by integrating spatially replicated multispecies detection-nondetection observations and the data on species geographic distributions. We determined abundance of 1,248 woody plant species at a 10 km grid square resolution over East Asian islands across subtropical to temperate biomes, which produced a metacommunity (i.e. species pool) SAD in four insular ecoregions along with its absolute size. The metacommunity SADs indicated lognormal-like distributions, which were well explained by the unified neutral theory of biodiversity and biogeography (UNTB) with protracted speciation, a mode of speciation intermediate between point mutation and random fission. Furthermore, the analyses yielded an estimate of speciation rate in each region that highlighted the importance of geographic characteristics in macroevolutionary processes and predicted the average species lifetime that was congruent with previous estimates. The estimation of macroscale SADs plays a remarkable role in revealing evolutionary diversification of regional species pools.


Entropy ◽  
2021 ◽  
Vol 23 (4) ◽  
pp. 464
Author(s):  
Frank Nielsen

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.


2018 ◽  
Vol 2018 ◽  
pp. 1-7 ◽  
Author(s):  
Hellen K. Mandela ◽  
Mugatsia H. Tsingalia ◽  
Mary Gikungu ◽  
Wilbur M. Lwande

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.


Author(s):  
Pema Lhamo ◽  
Ahmedul Kabir ◽  
Sayed Mohammad Nazim Uddin

Plant diversity in the wetlands of Phobji and Gangtey represents an important aspect of the overall wetland ecosystem. However, over the years, the increasing trend in population has initiated the building of many infrastructures and accommodations which lie at close proximity to the core wetland area. The plant diversity in human settled area and core undisturbed area was studied, with an objective to assess the influence of human settlement on the plant diversity. A belt transect method was used for the purpose of vegetation survey and Shannon Wiener diversity was calculated using the relative dominance. Plants were analyzed for their diversity, richness, dominance and invasive nature. Additionally, soil and water parameters were also tested to see the current situation of the pH and nutrient levels. A total of 136 species belonging to 39 families was identified in both the areas. The overall diversity index and species richness was found to be higher in the undisturbed areas. Soil analysis did not show much of a difference in physical and chemical parameters except for a slight difference in potassium content. Similarly, water parameters did not show much difference but only showed variation in calcium content. The findings of the study indicated towards the increasing influence of human settlement in the wetland.


2021 ◽  
Vol 15 ◽  
pp. 117863022110610
Author(s):  
Wubalem Genanaw ◽  
Girum Gebremeskel Kanno ◽  
Dawit Derese ◽  
Mekonnen Birhanie Aregu

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.


2016 ◽  
Vol 64 (2) ◽  
pp. 875 ◽  
Author(s):  
Gonzalo D. Rubio

There is a clear connection between basic taxonomy and biodiversity issues. Faunistic studies with a taxonomically comprehensive inventory of species provide an important source of quantitative compiled information concerning several regions. This information can be used in diversity analysis and have great potential in setting conservation priorities. The salticid spider fauna of Misiones is relatively well known; here this knowledge is used to generate Clarke & Warwick taxonomic diversity indices. Different ecoregional diversities contributing to information about biodiversity levels of salticids in Misiones and providing reference data for future studies are analyzed. Differences between the three ecoregions of the province were found, mainly southern savannas regarding the forests of northern Misiones.


2020 ◽  
Vol 6 (1) ◽  
pp. 54-60
Author(s):  
Khoiratul Hasanah ◽  
Ari Hayati ◽  
Hasan Zayadi

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


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 ◽  
...  

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.


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