ETUDE AGRO-ECOLOGIQUE DANS LE COMTE DE RIVIERE-DU-LOUP: ASPECT ECOLOGIQUE

1978 ◽  
Vol 58 (1) ◽  
pp. 117-128
Author(s):  
J. M. DESCHENES ◽  
J. C. ST-PIERRE
Keyword(s):  
Ecological Study ◽  
Ecological Factors ◽  
Vegetation Changes ◽  
Plant Association ◽  
Vegetation Survey ◽  
Land Utilization ◽  
Red Fescue ◽  
Plant Associations ◽  
Ecological Habitat ◽  
Successional Stages

Intensive studies of soil and vegetation were performed in Rivière-du-Loup County to identify various plant associations of meadows and pastures, describe the successional trends of each ecological habitat and establish a relationship between plant associations and various environmental factors. After vegetation survey and analysis, four plant associations and their successional trends were described. Each plant association was identified by the dominant species at the most advanced stage of secondary succession: (1) red fescue-bent grass association, (2) red fescue-Lindberg’s plume moss association, (3) bent grass–red fescue association, and (4) poverty grass–mouse-eared hawkweed association. All four plant associations were distributed in space according to the physiography and nature of the soils. Vegetation was highly influenced by age of sites. Young meadows and pastures were dominanted by timothy, red top, white clover and Canada bluegrass. Red fescue was very important on all 10 yr-old sites and remained so in all successional stages except in bent grass–red fescue and poverty grass–mouse-eared hawkweed associations. Vegetation changes with age depended on both ecological factors and land utilization. The results suggest that intensive soil studies and a rapid survey of vegetation would have provided results very similar to those obtained by a very detailed ecological study.

scholarly journals Ecological preference of the diving bell spider Argyroneta aquatica in a resurgence of the Po plain (Northern Italy) (Araneae: Cybaeidae)

2016 ◽  
Vol 48 (1) ◽  
pp. 9 ◽  
Author(s):  
Stefano Mammola ◽  
Riccardo Cavalcante ◽  
Marco Isaia
Keyword(s):  
Ecological Study ◽  
Aquatic Vegetation ◽  
Linear Models ◽  
Prey Availability ◽  
Ecological Factors ◽  
Northern Italy ◽  
Aquatic Life ◽  
Po Plain ◽  
Ecological Importance ◽  
Positive Effect

The diving bell spider <em>Argyroneta aquatica</em> is the only known spider to conduct a wholly aquatic life. For this reason, it has been the object of an array of studies concerning different aspects of its peculiar biology such as reproductive behavior and sexual dimorphism, physiology, genetic and silk. On the other hand, besides some empirical observations, the autoecology of this spider is widely understudied. We conducted an ecological study in a resurgence located in the Po Plain (Northern Italy, Province of Vercelli) hosting a relatively rich population of <em>Argyroneta</em> <em>aquatica</em>, aiming at identifying the ecological factors driving its presence at the micro-habitat level. By means of a specific sampling methodology, we acquired distributional data of the spiders in the study area and monitored physical-chemical and habitat structure parameters at each plot. We analyzed the data through Bernoulli Generalized Linear Models (GLM). Results pointed out a significant positive effect of the presence of aquatic vegetation in the plot. In addition, the presence of <em>A. aquatica</em> was significantly associated with areas of the resurgence characterized at the same time by high prey availability and low density of predators. Considering the ecological importance and rarity of this species, we update and revise the data on the distribution of <em>A. aquatica</em> in Italy.

scholarly journals Ecological and coenotical structure of the Regional Natural Monument «Chelyabinsk city pine forest» vegetation

2019 ◽  
Vol 8 (2) ◽  
pp. 38-44
Author(s):  
Nazar Nikolayevich Nazarenko ◽  
Maria Dmitrievna Novgorodova
Keyword(s):  
Distance Measure ◽  
Ecological Factors ◽  
Pine Forest ◽  
Forest Vegetation ◽  
Regime Changes ◽  
Forest Flora ◽  
Plant Associations ◽  
Synanthropic Species ◽  
Linkage Method ◽  
Natural Monument

The following paper deals with the ecological and coenotical structure of the Regional Natural Monument Chelyabinsk city pine forest vegetation. The estimation was done by a cluster analysis with Sorensen-Chekanovsky (Bray-Curtis) distance measure and a flexible beta group linkage method - by non-metric multidimensional scaling, phytoindication and general discriminant analysis algorithms. The flora and coenotical structure of Chelyabinsk city pine forest plant communities are characterized by significant anthropogenic transformation. Forest-margin and meadow, ruderal and synanthropic species are insinuating and naturalizing in pine forest communities actively and supplanting typical pine forest species off communities. The studied pine forest flora synanthropic index is 32 percent. 15 plant associations were detected; its flora, dominant and constant species, coenotical structure and biotopes were characterized by principal ecological factors. The biotopes series of ecological factors replacement were identified. Biotopes series are specified by forest stand ecological structure, that determining ecological regime changes from semi-light to semi-shade and from more arid to more damp. Also biotopes form series from wet more variable moistening bad-aerated not-acid and salt enriched soils to acid aerated poor soils with contrast arid moistening. The detected Chelyabinsk city pine forest biotopes are characterized by not so fluctuation of principal ecological factors.

scholarly journals Ramondo-Ostryetum carpinifoliae – a new association from the hop-hornbeam forests of the Sharri Mountains, Kosovo

Hacquetia ◽  
2019 ◽  
Vol 18 (2) ◽  
pp. 323-336
Author(s):  
Naim Berisha ◽  
Fadil Millaku ◽  
Bekim Gashi ◽  
Vlado Matevski
Keyword(s):  
Plant Community ◽  
Plant Communities ◽  
Plant Association ◽  
Limestone Habitat ◽  
Plant Associations ◽  
New Association ◽  
Ostrya Carpinifolia ◽  
Ramonda Myconi

Abstract In Europe, the genus Ramonda is represented with three species: Ramonda nathaliae, Ramonda serbica and Ramonda myconi. The first two are endemic Balkan species that are distributed also in Kosovo. These species grow in limestone as well as serpentine substrates, forming chasmophytic vegetation. The species Ramonda nathaliae is found in Macedonia, Greece, Serbia and in two localities in Kosovo, in the Sharri Mountains (Luboten and Gotovushë). R. nathaliae forms the following plant associations in the serpentines of Macedonia: Asplenio­Ramondetum nathaliae and Scorzonero-Ramondetum nathaliae, and the Achilleo­Ramondetum nathaliae in limestone substrates. Ostrya carpinifolia is charateristic species in Querco pubescentis-Ostryetum carpinifoliae, Ostryo-Fagetum, Querco-Ostryetum carpinifoliae and Corylo colurnae-Ostryetum carpinifoliae. This paper presents plant communities of Ramonda nathaliae and Ostrya carpinifolia in a limestone habitat, where the proposed new plant association named Ramondo­Ostryetum carpinifoliae ass. nova. is described. This plant community belongs to the class Quercetea pubescentis, order Quercetalia pubescenti­petraeae and alliance Fraxino orni­Ostryion. It was found and described on the limestone substrate on Mt. Luboteni (at 960–982 m a.s.l.).

scholarly journals Plant associations for three sawfly species (Hymenoptera, Tenthredinidae) in the Pacific Northwest

2019 ◽  
Vol 74 ◽  
pp. 27-33
Author(s):  
Quinlyn Baine ◽  
Chris Looney
Keyword(s):  
Pacific Northwest ◽  
Plant Association ◽  
Plant Associations ◽  
The Pacific

Plant associations are newly recorded for three tenthredinid species in the Pacific Northwest. A single Monardis pulla D.R. Smith, 1969 emerged from a chamber inside a cynipid gall on Rosa nutkana C. Presl. (Rosaceae). This is the first plant association record for M. pulla. Two Aphilodyctium fidum (Cresson, 1880) emerged from a stem and cynipid gall of Rosa rugibinosa Linnaeus, 1758, respectively. Several Rhogogaster lateraria (Cresson, 1880) eggs were discovered on Castilleja sp., which has no previously recorded sawfly associations.

scholarly journals Association distribution characteristics of natural and artificial Larix gmelinii forests along environmental gradients in northeast China

2019 ◽  
Author(s):  
Xiaohang Bai ◽  
Jinghua Yu ◽  
Shusheng Yuan ◽  
Yihong Tan
Keyword(s):  
Species Diversity ◽  
Northeast China ◽  
Larix Gmelinii ◽  
Annual Precipitation ◽  
Environmental Drivers ◽  
Slope Aspect ◽  
Scientific Management ◽  
Plant Association ◽  
Natural Forests ◽  
Plant Associations

Abstract Background: Larix gmelinii forest is one of coniferous forests in cold-temperate zone, which is a vital part of national strategic landscape of ecological security of China. Plant association distribution is different in natural and artificial Larix gmelinii forests, meanwhile, determining mechanisms in typical associations of Larix gmelinii forests still need to be explored. The study focused on which environmental factors actuated association distribution of natural and artificial Larix gmelinii forests in northeast China. Two-way indicator species analysis (TWINSPAN) and canonical correspondence analysis (CCA) were used to classify plant associations and explored the relationship between species and environment. Results: All the plots (n=175, size=30 m×30 m) of Larix gmelinii forests were classified into 6 plant associations by TWINSPAN. Species diversity in natural forests were higher than that in artificial forests. Ass.III and Ass.IV only appeared in natural forests, meanwhile, Ass.VI only appeared in artificial forests. The primary environmental drivers of species diversity patterns in natural forests were annual mean temperature, followed by annual precipitation, elevation, slope aspect, and canopy density. However, elevation and annual precipitation had strong effects in determining association distribution in artificial forests. Conclusions: Plant association distribution showed habitat preferences, besides, natural forests had higher species diversity and more resistance than artificial forests. The study can be used as a reference for Larix gmelinii forest ecosystem protection in northeast China and a theoretical basis for scientific management in similar areas.

scholarly journals Social and Economic Variables Related with Paraquat Self-Poisoning: an Ecological Study

2019 ◽  
Author(s):  
Jefferson Buendia ◽  
Gabriel Jaime Restrepo Chavarriaga ◽  
Andres F. Zuluaga
Keyword(s):  
Gini Index ◽  
Private Health Insurance ◽  
Ecological Study ◽  
Multivariate Analyses ◽  
Ecological Factors ◽  
Oral Route ◽  
Global Burden ◽  
Economic Variables ◽  
Socio Economic Variables ◽  
The Relationship

Abstract Background Paraquat self-poisonings constitute a significant contributor to the global burden of suicide.Our aim was to evaluate the relationship between social and economic variables with the incidence of self-poisoning with Paraquat in the northeast of Colombia.Methods Records of 154 cases of self-poisoning with Paraquat and several socio-economic variables of six regions of northeast of Colombia were analyzed. Results Most of the cases were mestizos, farmworkers, between 20 and 29 years, with intentional exposure using the oral route. Multivariate analyses revealed significant associations among the incidence of self-poisoning with PQ with the ecological factors such as poverty greater than 30% (IRR 15.9 IC95% 5.56-44.72), land Gini index <0.7 (IRR 7.11 IC95% 3.58-14.12), private health insurance <40% (IRR 3.39 IC95% 1.30-8.82) and planted area >10% (IRR 2.47 IC95% 1.60-3.80).Conclusion There is a relationship between ecological factors and, as such, this study opens the way to further developments in the field.

scholarly journals Ecologicaland phenological characteristics of macromycetes of the Goleniowska Woods

2014 ◽  
Vol 21 (2) ◽  
pp. 143-164 ◽  
Author(s):  
Stefan Friedrich
Keyword(s):  
Ecological Factors ◽  
Plant Associations

The paper describes effects of some ecological factors on the macromycetes development and singles out the fungi species typical of the 8 phenological seasons in various plant associations.

Density and dispersion of two species of kangaroo in relation to habitat

1964 ◽  
Vol 12 (2) ◽  
pp. 238 ◽  
Author(s):  
GJ Caughley
Keyword(s):  
Quantitative Difference ◽  
Plant Association ◽  
The Past ◽  
Plant Associations ◽  
Preferred Habitat ◽  
Grey Kangaroo ◽  
Random Dispersion

The dispersion of red and grey kangaroo faeces is usually random in any one plant association although the animals themselves are contagiously distributed. However, groups of kangaroos show a random dispersion in contrast to the contagious dispersion of groups of sheep. The density and dispersion of grey kangaroo faeces correlates with the thickness of cover, probably reflecting selection in the past by marsupial carnivores which are now extinct on the mainland. The density and dispersion of neither kangaroo species correlates with the density or dispersion of the woodland canopy. Although both species of kangaroo utilize all of the plant associations studied, there is a quantitative difference in preferred habitat in that the ratio of densities differs between associations.

The arboreal ant community visiting extrafloral nectaries in the Neotropical cerrado savanna

2010 ◽  
Vol 3 (1) ◽  
pp. 3-27 ◽  
Author(s):  
Carla Ribas ◽  
Paulo Oliveira ◽  
Tathiana Sobrinho ◽  
José Schoereder ◽  
Marcelo Madureira
Keyword(s):  
Host Plants ◽  
Ecological Factors ◽  
Extrafloral Nectaries ◽  
Food Sources ◽  
Ant Community ◽  
Plant Associations ◽  
Cerrado Savanna ◽  
High Incidence ◽  
The Impact

AbstractThe cerrado savanna of Brazil embraces an area of approximately 2 million km2, in which vegetation physiognomies may vary from open grassland to forest with a discontinuous herbaceous layer. Here we describe the main ecological factors accounting for the prevalence of ants on cerrado foliage, and present a general characterization of the arboreal ant fauna of this savanna. The high incidence of ants on cerrado foliage results mostly from the wide occurrence of predictable liquid food sources in the form of extrafloral nectaries (EFNs) and insect honeydew, which act as efficient promoters of ant activity on vegetation. In addition, stem galleries and cavities constructed by boring beetles and insect galls create a nesting space frequently used by arboreal ants. Specific studies involving ants, herbivores and plants are reported to demonstrate the impact that foliage-dwelling ants can have on phytophagous insects, herbivory levels, and ultimately on host plants. These studies show that: (i) ants visit EFNs and likely benefit from this resource; (ii) EFN-gathering ants can benefit particular plant species by reducing herbivory and increasing plant fitness; (iii) presence of EFNs does not affect ant species richness within a given tree; (iv) there is not a particular ant species composition typical of plants with EFNs; (v) although plants with EFNs are visited by more ant individuals than non-nectariferous plants, this visitation pattern does not translate into lower numbers of herbivores on the nectariferous plant community. We suggest some promising research avenues to elucidate how community-level parameters can be tied to the ecology of ant-plant associations in cerrado.

scholarly journals Social and Economic Variables Related with Paraquat Self-Poisoning: an Ecological Study

2020 ◽  
Author(s):  
jefferson buendia ◽  
Gabriel Jaime Restrepo Chavarriaga ◽  
Andres F. Zuluaga
Keyword(s):  
Gini Index ◽  
Private Health Insurance ◽  
Ecological Study ◽  
Multivariate Analyses ◽  
Ecological Factors ◽  
Oral Route ◽  
Global Burden ◽  
Economic Variables ◽  
Socio Economic Variables ◽  
The Relationship

Abstract Background Paraquat self-poisonings constitute a significant contributor to the global burden of suicide.Our aim was to evaluate the relationship between social and economic variables with the incidence of self-poisoning with Paraquat in the northeast of Colombia. Methods Records of 154 cases of self-poisoning with Paraquat and several socio-economic variables of six regions of northeast of Colombia were analyzed. Results Most of the cases were mestizos, farmworkers, between 20 and 29 years, with intentional exposure using the oral route. Multivariate analyses revealed significant associations among the incidence of self-poisoning with PQ with the ecological factors such as poverty greater than 30% (IRR 15.9 IC95% 5.56-44.72), land Gini index <0.7 (IRR 7.11 IC95% 3.58-14.12), private health insurance <40% (IRR 3.39 IC95% 1.30-8.82) and planted area >10% (IRR 2.47 IC95% 1.60-3.80). Conclusion There is a relationship between ecological factors and, as such, this study opens the way to further developments in the field.

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