scholarly journals Spatial structure of Globularia bisnagarica L. (Plantaginaceae, Magnoliopsida) coenopopulations

Author(s):  
A. O. Kondratieva ◽  
A. S. Parkhomenko ◽  
A. V. Bogoslov ◽  
I. V. Shilova ◽  
A. S. Kashin

The paper presents the results of the spatial distribution analysis of 18 Globularia bisnagarica L. coenopopulations in the Saratov, Samara, Ulyanovsk and Orenburg regions and the Republic of Tatarstan. The analysis was carried out with the Spatstat package of the R environment for statistical computing. The research reveals an aggregation tendency for the G. bisnagarica coenopopulations. It is suggested that this tendency may be attributed to the prevalence of seed reproduction and certain peculiarities of dissemination (barochory) in the studied coenopopulations as well as to the confinement of the species to eroded landforms (slopes of watersheds, gullies, runoff hollows, etc.) characterized by high heterogeneity of environmental conditions. It has been established that the majority of G. bisnagarica coenopopulations grow in heavily or moderately sodded habitats. Nevertheless, in the studied communities, G. bisnagarica occurs abundantly and dominates along with Stipa pennata, Bromus inermis, Salvia nutans, Elytrigia repens, Poa compressa, etc. Finally, the spatial structure of G. bisnagarica coenopopulations is impacted by the interspecific competition in calciphilous phytocenoses under the invasion of eurybiontic steppe grasses.

2015 ◽  
Vol 41 (1) ◽  
pp. 41-47
Author(s):  
Jelena Vaitkevičienė ◽  
Aušra Kumetaitienė

Research on landscape stability of regional parks, the status and conditions of the objects and attributes of natural and cultural heritage serve a significant contribution to the survey of the properties of the national heritage possessed in the preserved areas of the Republic of Lithuania. The objective of this article is the analysis of visual landscape resources of Asveja Regional Park in terms of the current state and conditions, changes and modifications within territorial sites as well as with regard to the accumulation and concentration of the objects, their scope and extent. It is possible to assess the efficiency and expediency of an environmental impact taking into consideration research observations. The area of Asveja Regional Park significant for an intense anthropogenic environmental impact and defined in monitoring data sheets and records of Asveja Regional Park referring to 2005–2010 has been selected. Monitoring has been carried out by the Authority of Asveja Regional Park according to the Lithuanian State Environmental Monitoring Program. In order to solve the conflict between society and the environment, the project preconditioned by the use of natural resources and the preservation of valuable objects has been developed. Study on landscape monitoring has been carried out at the local level. It has been fixed within the selected territories, namely, standardised reference sites chosen on the basis of the geosystem and targeted on geophysical–geochemical sensitivity and technogenization with preference for the analysis of the most vulnerable geopotencial territories, i.e. nature reservations, protected areas, shores and the coastlines of lakes providing a wide range of recreational potential. Natural and cultural heritage objects violating regulations on requirements for landscape preservation have been observed in the determined standardized areas as visual resources of the regional park landscape. In order to determine the territorial dispersion of the infringements of requirements for landscape protection, the authors have performed a spatial distribution analysis of visual observation targets calculating nuclear or kernel density. Weight points of requirements for the items violating landscape protection have been attributed thus considering the monetary value of the prescribed fines (following regulations on the specific type of the caused damage). The analysis of the study on specified spatial distribution has been accomplished involving some groups of objects violating requirements for landscape protection. Within the conducted research, the authors investigated the targets that violated requirements for landscape protection and made use of the recorded data. The available findings derive a conclusion that a major part of infringements are considered as recreation violations (40%); violations in usage, trespassing, visiting forests and woodlands (5%) comprise a minor part. In general, the greatest accumulation of infringements are determined to be located in the western and south-eastern part of Asveja Regional Park where their intensity exceeds more than 6 times the concentration of infringements in other investigated areas and territories.


2014 ◽  
pp. 411-419
Author(s):  
Ivan Marinkovic

Ethnic homogeneity of settlements, or in other words, formation of ethnically homogeneous settlements in ethnically heterogeneous environment, such as Vojvodina, as well as the regions of Raska and Pcinja, is the issue which will be discussed in this paper. The analysis involves total population according to their ethnic affiliation (the 2011 Census), at the level of settlements. The estimates on the number of Albanian population at the level of settlements were made for the needs of this paper considering the fact that the census was not successful on the entire territory of the Republic because the ethnic Albanian boycotted it. Spatial distribution analysis and the determination of majority of population at the level of settlements represent the research focus of the paper. Furthermore, the aim of this paper was to point out certain ethnic characteristics of Serbian population (excluding Kosovo and Metohija), with the emphasis on the continuous trend of increasing number of people who do not want to declare their ethnic affiliation.


1996 ◽  
Vol 112 (13) ◽  
pp. 907-914 ◽  
Author(s):  
Katsuaki KOIKE ◽  
Yoshifumi NOGUCHI ◽  
Hiroshi IWASAKI ◽  
Katsuhiko KANEKO

2019 ◽  
Vol 53 (5) ◽  
pp. 417-422
Author(s):  
P. De los Ríos ◽  
E. Ibáñez Arancibia

Abstract The coastal marine ecosystems in Easter Island have been poorly studied, and the main studies were isolated species records based on scientific expeditions. The aim of the present study is to apply a spatial distribution analysis and niche sharing null model in published data on intertidal marine gastropods and decapods in rocky shore in Easter Island based in field works in 2010, and published information from CIMAR cruiser in 2004. The field data revealed the presence of decapods Planes minutus (Linnaeus, 1758) and Leptograpsus variegatus (Fabricius, 1793), whereas it was observed the gastropods Nodilittorina pyramidalis pascua Rosewater, 1970 and Nerita morio (G. B. Sowerby I., 1833). The available information revealed the presence of more species in data collected in 2004 in comparison to data collected in 2010, with one species markedly dominant in comparison to the other species. The spatial distribution of species reported in field works revealed that P. minutus and N. morio have aggregated pattern and negative binomial distribution, L. variegatus had uniform pattern with binomial distribution, and finally N. pyramidalis pascua, in spite of aggregated distribution pattern, had not negative binomial distribution. Finally, the results of null model revealed that the species reported did not share ecological niche due to competition absence. The results would agree with other similar information about littoral and sub-littoral fauna for Easter Island.


2021 ◽  
Vol 33 (8) ◽  
pp. 085102
Author(s):  
Fernando Luis Esteban Florez ◽  
Tyler Thibodeau ◽  
Toluwanimi Oni ◽  
Evan Floyd ◽  
Sharukh S. Khajotia ◽  
...  

Nematology ◽  
2007 ◽  
Vol 9 (1) ◽  
pp. 131-142 ◽  
Author(s):  
Maria Viketoft

AbstractThis study describes the nematode community in a semi-natural grassland and investigates if certain individual plant species can cause a spatial structure in the nematode fauna. Nematode communities were analysed in soil under Trifolium repens, Festuca ovina and from randomly taken samples. Seventy-nine nematode genera were identified. Some of the species found have not previously been reported from Sweden. Multivariate analysis separated the nematode communities associated with the two selected plant species from each other, and several individual nematode genera differed in abundance between the plant species. Trifolium repens supported greater populations of the plant feeder Tylenchorhynchus and the bacterial feeders Eucephalobus, Chiloplacus, Eumonhystera and Panagrolaimus, but fewer numbers of the bacterial feeder Achromadora. Soil under F. ovina contained more nematodes from the family Alaimidae. A comparison is given with other studies from grassland systems in Sweden.


2021 ◽  
Vol 7 (12) ◽  
Author(s):  
A. Nasirovа

The article presents the results of a study of the mallow genus — Malva L. characteristic of the meadow vegetation of the Ganja-Gazakh region of the Republic of Azerbaijan. From 11 species of the genus Malva L. distributed on the territory of Azerbaijan, 4 species (Malva sylvestris L., Malva nicaeensis All., Fl. Pedem, Malva pusilla Sm., Malva parviflora L.) are found in the Ganja-Gazakh region. The species M. parviflora was first identified by us in this territory. The species M. parviflora and M. sylvestris are not widely distributed in this territory. The structure of populations of M. pusilla and M. nicaeensis species was studied. 7 populations in which M. pusilla and M. nicaeensis species are distributed were phytocoenological evaluated. 3 cenopopulations in which the species M. nicaeensis is common were evaluated in different years. All groups of plant ontogenesis are found in the studied populations. It was found that in different years in the populations of these two species of the genus mallow, recovery is weak, and aging is intense. During the analysis of the population structure, reproduction indices — Ib and aging — Iq were determined, which are important population indicators. The integral characteristic of the demographic structure of M. pusilla and M. nicaeensis species is determined, the populations are estimated, the composition, age (height) and the degree of effectiveness of their ontogenesis are studied. The dynamics of changing ontogenesis in the cenopopulations of M. pusilla and M. nicaeensis species in various environmental conditions, depending on the positive or negative influence of its factors on the structure of ontogenesis, is revealed.


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