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AI ◽  
2021 ◽  
Vol 2 (4) ◽  
pp. 621-635
Author(s):  
Vincent Margot ◽  
George Luta

Interpretability is becoming increasingly important for predictive model analysis. Unfortunately, as remarked by many authors, there is still no consensus regarding this notion. The goal of this paper is to propose the definition of a score that allows for quickly comparing interpretable algorithms. This definition consists of three terms, each one being quantitatively measured with a simple formula: predictivity, stability and simplicity. While predictivity has been extensively studied to measure the accuracy of predictive algorithms, stability is based on the Dice-Sorensen index for comparing two rule sets generated by an algorithm using two independent samples. The simplicity is based on the sum of the lengths of the rules derived from the predictive model. The proposed score is a weighted sum of the three terms mentioned above. We use this score to compare the interpretability of a set of rule-based algorithms and tree-based algorithms for the regression case and for the classification case.


Author(s):  
S. Alvarez Cortez ◽  
R. Peña Murillo ◽  
D. Román Robalino

The present investigation proposes to study the ecosystem services linked to water and floristic diversity in the Igualata paramo of the Hualcanga region; 5 sampling plots of 25 m2 were installed, with 4 subplots of 1 m2. 30 samples of terrestrial vascular plants were obtained, identifying 17 botanical families, 26 genera, and 27 species, and 1 lichen and 1 moss of unidentified family and genus. It was determined that the species that stands out with the highest importance value index was Lachemilia orgiculata with 44.06%, because the species was found in 4 of the 5 study plots. In second place we have Calamagrostis intermedia species with 8.21%, while the species Vicea sp. was the species with the lowest importance value index of 0.50%, being the species with the lowest number of individuals. The Rosaceae family presented the highest index with 39.61%. The Poaceae and Asteraceae families also present dominance in this ecosystem with values of 9.63% and 5.79%, respectively. According to the Shannon index, plots P2 and P4 were those with high diversity, which corroborates with what was obtained in the Simpson index; the Sorensen index showed us that plots P4 and P5 are very similar, plots P1 and P3 are fairly similar, and the remaining plots are dissimilar, which indicated that vegetation can be found in certain areas of the investigation. The water flow supplying the resident families of the region was found to be 8.12 L/s, and its ecological flow is of 0.83 L/s, having a flow that satisfies the needs of the inhabitants. Keywords: caudal, ecological flow, ecosystem paramo, ecosystem services, floristic diverity, indices of diversity. Resumen La presente investigación propone: estudiar los servicios ecosistémicos ligados al agua y diversidad florística en el páramo del Igualata regional Hualcanga; se instalaron cinco parcelas de muestreo de 25 m2 con 4 sub parcelas de 1 m2, se obtuvo 30 muestras de plantas vasculares terrestres, identificando 17 familias botánicas, 26 géneros y 27 especies, además se colectó 1 liquen y 1 musgo de familia, género y especie no identificado. Se determinó que la especie que sobresale con mayor índice de valor de importancia fue Lachemilia orgiculata con un 44,06%, esto se debe a que la especie se encontraba en 4 de las 5 parcelas de estudio, en segundo lugar, tenemos a Calamagrostis intermedia especie con 8,21%, mientras que la especie Vicea sp. fue la que menor índice de valor de importancia presentó con un 0,50% esto se debe a que fue la especie con menor cantidad de individuos. La familia Rosaceae presentó el mayor índice con 39,61%, las familias Poaceae, y Asteraceae presentan una dominancia en este ecosistema con valores de 9,63% 5,79%, respectivamente. De acuerdo al índice de Shannon las parcelas 2 y 4 son las que poseen diversidad alta que se corrobora con lo obtenido en el índice de Simpson; en el índice de Sorensen nos muestra que las parcelas P4 vs P5 son muy similares las parcelas P1 y P3 son medianamente similares y las parcelas restantes son disimiles lo que indica que la vegetación se puede encontrar en ciertas zonas de la investigación. El caudal que posee la Regional es de 8,12 L/s, abasteciendo a las familias y su caudal ecológico es de 0,83 L/s teniendo un caudal que satisface las necesidades de los pobladores. Palabras clave: caudal, caudal ecológico, diversidad florística, ecosistema páramo, índices de diversidad, servicios ecosistémicos. 


2021 ◽  
Vol 22 (2) ◽  
Author(s):  
Amina Belguidoum ◽  
Takia Lograda ◽  
Messaoud Ramdani

Abstract. Belguidoum A, Lograda T, Ramdani M. 2021. Diversity and distribution of epiphytic lichens on Cedrus atlantica and Quercus faginea in Mount Babor Forest, Algeria. Biodiversitas 22: 887-899. Information about lichen diversity in Algeria is limited despite their important role as biological indicators of ecosystem health. The aim of the study was to carry out an inventory of epiphytic lichens in the Mount Babor Forest on two types of phorophytes (host trees), i.e., Cedrus atlantica and Quercus faginea, in varying altitudinal gradients and the diameter of host tree. The similarity of the sampled sites was assessed by the Sorensen index (β). Sixty-six species of epiphytic lichens were identified, which belong to 24 families and 38 genera. C. atlantica hosted a higher number of species than Q. faginea. The majority of lichen on C. atlantica belonged to the Parmeliaceae family, whereas those on Q. faginea belonged to the Physciaceae family. Crustose and foliose lichens were the most common species in the study area. The results showed the existence of a distinct relationship between the parameters of the distribution (i.e., tree diameter, elevation) and the specific lichen richness. The greatest number of lichen species (59 species) was observed on large diameter trunks (41-60 cm). Lichen diversity increased along with the increase in altitude. Sorensen’s similarity index revealed the presence of heterogeneity in the community composition of lichen vegetation.


Plants ◽  
2020 ◽  
Vol 9 (12) ◽  
pp. 1654
Author(s):  
Antonio Galán-de-Mera ◽  
José Campos-de-la-Cruz ◽  
Eliana Linares-Perea ◽  
Juan Montoya-Quino ◽  
Iván Torres-Marquina ◽  
...  

This work is a phytosociological approach to the montane rainforests of Peru with the aim of advancing on the diversity of plant communities, which we had already begun in previous research. From 364 phytosociological plots and 3389 species of the South American tropics, we have developed a cluster, using the Sørensen index, to know the similarities between the forests and their parallelism with bioclimatic conditions. After studying the existence of characteristic groups of the Peruvian forests, we have established different communities and phytosociological units for Peru. As a result, we have described seven associations, within three new alliances, which are gathered in the new order Saurauio peruvianae-Condaminetalia corymbosae of the new class Morello pubescentis-Myrsinetea coriaceae. In addition, two associations have been described within the class Pruno rigidae-Oreopanacetea floribundae (mesotropical laurel-like forests), and three for the class Alnetea acuminatae (alder forests and palm groves). The humid forests of Peru are closer to those of Ecuador and to those of the set formed by the three Colombian mountain ranges than to those of Bolivia and Argentina, due to the common flora these share with areas of Paraguay and even of the Parana River region.


2020 ◽  
Vol 21 (11) ◽  
Author(s):  
SRI RAHAYU PRASTYANINGSIH ◽  
Suryo Hardiwinoto ◽  
MUSYAFA MUSYAFA ◽  
CAHYONO AGUS DWI KORANTO

Abstract. Prastyaningsih SR, Hardiwinoto S, Musyafa, Koranto CAD. 2020. Diversity of termites (Isoptera) on industrial forest plantation of Eucalyptus pellita stands of tropical ecosystem in Riau, Indonesia. Biodiversitas 21: 5498-5505. Eucalyptus pellita is an alternative tree species for pulp and paper of industrial forest plantation. One of the forest plantation’s negative effect is the loss of biodiversity and vulnerable to pest and disease. Termites are one of the pests attacking the forest plantations and play an important role in the ecological process. Need a better understanding of the termite role ecosystem process in E. pellita stands. This research aimed to determine the diversity of termite species found in E. pellita stands at different rotation and ages of stands. Termite diversity sampled by the transect sampling method in the 4th and 5th rotation with four-level ages (1, 2, 3, 4-years-old). The transect area was divided into 24 plots (100 m x 2 m). The termites in the Eucalyptus stand consist of two families (Termitidae and Rhinotermitidae), five subfamilies (Termitinae, Macrotermitinae, Nasutitermitinae, Rhinotermitinae, and Coptotermitinae), and eight species (Discupiditermes nemorosus, Macrotermes gilvus, Termes rostatus, Amitermes dentatus, Microcerotermes sp., Nasutitermes matangensis, Schedorhinotermes medioobscurus, and Coptotermes havilandi). The diversity index (H) in the 4th rotation was 1.95, while in the 5th rotation was 1.63, with a similarity in the Sorensen Index of 87.71%. The existence of termites is dominated by the wood feeder group. The species richness of the termites at the two rotations increased with the increase of the stand age.. The relative abundance composition of termites in the 5th rotation, is higher than the 4th rotation. Termite occurrence was influenced by necromass, tree biomass, humidity, and temperature.


2020 ◽  
Vol 17 (41) ◽  
pp. 2-15
Author(s):  
Marcelo Silva De Lucena ◽  
Alan Cauê De Holanda ◽  
Allyson Rocha Alves

In the Caatinga, the maintenance of forest ecosystems depends on natural regeneration and several factors that can act in two ways: 1) provide the perpetuation of communities composheed of few species that dominate the adult and saplings strata, resulting in floristic similarities; 2) provide local differentiation between adult and saplings strata. However, these relationships remain poorly understood, as it is not known whether the factors acting on a local scale favor the floristic similarity between the adult and saplings strata or if these patterns are found in conserved and anthropized areas. This work evaluated the floristic similarity between the adult and saplings strata of hyperxerophilous caatinga woody-shrubby vegetation in conserved and anthropized areas. In two areasof conserved and anthropized hyperxerophilous Caatinga, adult and saplings individuals were measured and floristic richness and qualitative floristic similarity were evaluated. The floristic similarity between the adult and saplings strata was statistically compared using the Chao-Sørensen index. In both sites, although there was a large number of species exclusive to the adult stratum, the Chao-Sørensen index indicates high floristic similarity between strata. The analysis of this behavior together with the assessment of community structure shows that few species can be responsible for the key processes that structure and control the main mechanisms of persistence of these ecosystems. This can be attributed to the existence of locally uniform conditions that can define the dominance of adapted species groups.


2020 ◽  
Vol 2020 ◽  
pp. 1-9
Author(s):  
Eveleise Samira Martins Canto ◽  
Ana Claúdia Alves Cortez ◽  
Josiane Santana Monteiro ◽  
Flavia Rodrigues Barbosa ◽  
Steven Zelski ◽  
...  

Aquatic ecosystems in tropical forests have a high diversity of microorganisms, including fungi, which are important decomposers of submerged wood. Despite the importance of their role in decomposition, research concerning the diversity of freshwater fungi from Brazilian Amazonian environments is scarce. The aim of this work was to describe the composition and diversity of fungi present on submerged wood in two lakes of the Brazilian Amazon (State of Pará). Fragments of decaying wood (30 samples per lake) were collected from the Lakes Juá and Maicá. The wood samples were inspected for 6 months in the presence of fungal reproductive structures. Fungi observed in the wood were identified morphologically. Twenty-three taxa were identified in the Lake Juá (10 sexual and 13 asexual) and 26 taxa in the Lake Maicá (17 sexual, 9 asexual). ITS sequences were obtained for 14 taxa to aid in identification. In the Lakes Juá and Maicá, the diversity indices were H': 2.6514 and H': 2.8174, respectively. The Sørensen index of the fungal communities in the studied lakes was 0.3673. This study is the first to describe the fungal biodiversity of two important aquatic environments in Pará, Brazil.


Zoodiversity ◽  
2020 ◽  
Vol 54 (6) ◽  
pp. 487-492
Author(s):  
Ilyashenko ◽  
Luchnikova ◽  
Danilov ◽  
Kovalevsky ◽  
Zubko

We studied the dynamics of mouse-like rodent communities in the area of self-growing vegetation, which had undergone deforestation. The research is based on the results of continuous monitoring conducted from 1978 to 2019. Pitfall traps was the method of catching small mammals during the monitoring period. We used Simpson’s Diversity Index to quantify species diversity. The community similarity was evaluated by the percentage of species through Czekanowski-Sørensen Index. The studies were carried out near the “Azhendarovo” Biological Station (54°45ʹ N, 87°01ʹ E). The results of the studies showed that natural primeval communities of the taiga zone before deforestation were characterized by a multidominant structure. The dominant group included the Alexandromys oeconomus Pallas, 1776, and codominant species are represented by the genus Clethrionomys. A characteristic feature of the small mammals’ population of taiga forests is the preponderance of the Apodemus peninsulae (Thomas, 1907) over the Apodemus agrarius Pallas, 1771. On meadowlands, the genus Microtus voles prevailed. These were largely the Al. oeconomus, which accounted for 43% of all mouse-like rodents. After the deforestation, the structure changed. In the early stage of deforestation, the dominant species among rodents was the Al. oeconomus. The composition of dominant species in the recovering areas of cut-down taiga began to approach to the original state 40 years after the deforestation. Meadow communities followed the path of transformation, having no analogs in the initial period and were characterized by a significant amount of ruderal vegetation.


2018 ◽  
Vol 17 (3) ◽  
Author(s):  
Wawan Sujarwo ◽  
I Nyoman Lugrayasa ◽  
Farid Kuswantoro

The trade process makes traditional market able to become a pool of traditional knowledge for various local wisdoms that develop in the local community, including the use of plants. This study aims to document the traditional uses of plant species traded in three traditional markets in Tabanan regency. Data collection was carried out by semi-structured interview toward 64 traders of Baturiti, Marga, and Tabanan traditional markets, respectively. Data analysis was performed quantitatively by calculating the use value index, and some ecological indices, such as diversity index, margalef index, pielou index, sørensen index, cluster analysis, and principal component analysis. Qualitative analysis was also used to tabulate and presented the data into tables and figures. The study documented 52 plant species belonging to 48 genera and 30 families. Herbs are the most widely used habitus, and Zingiberaceae is the most widely used plant family. The most widely used use-category is condiments, and Cocos nucifera is a plant species with the highest use-value. The study also showed a highly plant diversity, which is traded in each market, with slightly different similarities. Cluster analysis and PCA showed that there is a little difference in plants species traded in three traditional markets. Differences in altitude may affect the diversity of plant species traded, including the buyer's preference (community).


2018 ◽  
Vol 30 (0) ◽  
Author(s):  
Hugo Marques ◽  
João Henrique Pinheiro Dias ◽  
Igor Paiva Ramos

Abstract Aim β diversity was used as an indicator to test the hypothesis that a fishway can increase river connectivity, as a reduction in the value of this metric indicates greater similarity among fish assemblages. Methods Quarterly sampling was performed with gillnets upstream and downstream of the Porto Primavera dam, Upper Paraná Basin, before the opening of the fishway between February 1999 and May 2001, and between February 2003 and May 2005 with the fishway in operation (10 samples per period/site). The correlation between the fish assemblages and sites was verified by applying two Mantel tests (downstream versus upstream before and one equivalent after the fishway) using the distance matrices generated by the Bray‐Curtis index. The β diversity between downstream and upstream was calculated using the Sørensen index for each sample for the comparison of such values before and after the operation of the fishway, which were tested with Asymptotic Wilcoxon-Mann-Whitney Test. To summarize changes in the structure of the fish assemblages between the sites and periods nonmetric multidimensional scaling (NMDS) was applied based on Bray-Curtis dissimilarities, using multi-response permutation procedures (MRPP). Results The Mantel tests showed no correlation between the upstream and downstream assemblages before the operation of the fishway but greater correlation after. β diversity was lower after than before the fishway, representing an increase in similarity between downstream and upstream with the fishway. MRPP analysis indicated that the fish assemblages between the sites differed more than was expected by chance, with smaller divergence between the sampling sites after the fishway (A = 0.08) than before it opened (A = 0.09). Conclusions Although fishways remain an incipient and controversial theme for neotropical fish, the Porto Primavera fishway appears to be effective in terms of the restoration of connectivity.


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