scholarly journals The influence of Picea abies on herb vegetation in forest plant communities of the Veporské vrchy Mts.

2010 ◽  
Vol 56 (No. 2) ◽  
pp. 58-67 ◽  
Author(s):  
F. Máliš ◽  
J. Vladovič ◽  
V. Čaboun ◽  
A. Vodálová

Natural mixed beech-fir forests were quite widely replaced by spruce dominated stands in Slovakia. Given the demands on the assessment of the forest status as well as on stopping the biodiversity loss it is required to evaluate the influence of <I>Picea abies</I> (L.) Karst. on the species composition. In a case study from the Veporské vrchy Mts. natural beech dominated forests were compared to stands with different spruce proportion. Within three groups of relevés with no, less and more than a half proportion of <I>Picea abies</I> the species diversity and Ellenberg indicator values were compared. The response of particular species to the proportion of <I>Picea abies</I> was evaluated by partial relation in direct gradient analysis. The increasing spruce proportion causes particularly higher occurrence of acidophytes and a decrease in nitrophytes. Species with the highest positive response to spruce are mostly shallow-rooted or characteristic of natural spruce forests. Greater richness along with the highest diversity was found in mixed stands with less than a half proportion of <I>Picea abies</I>. The most significant difference in species composition was between natural and spruce dominated stands. However the proportion of <I>Picea abies</I> does not reduce the species diversity in general, it causes significant changes in the species composition. As the results show, to avoid the negative effect and loss of phytodiversity it is required not to grow spruce dominated stands out of the natural occurrence of <I>Picea abies</I>.

1970 ◽  
Vol 17 (1) ◽  
pp. 25-31 ◽  
Author(s):  
Anita Pokharel ◽  
Madhu Chhetri ◽  
Chiranjibi P Upadhyaya

Limited information is available on the species composition, above ground biomass and its relations to grazing in a trans-Himalayan rangeland. Its assessment is essential for long term conservation and management. In the present study, we compared species composition, phenology, diversity index and biomass between controlled (without grazing) and open (free grazing) plots to assess the effects of grazing in the selected experimental sites of Upper Mustang during July and November 2005. Species encountered were classified as high, medium, low and non palatable and in three life form categories-grasses, shrubs and forbs. The experimental sites are dominated by forbs (80%) followed by grasses (15%) and shrubs (5%). Disturbance caused by grazing affects the phenological characteristics of the plant community. Result also reveals that species diversity, maximum possible diversity, evenness and species richness was higher in the grazed plots during July and November. A comparison of the aboveground biomass in July showed that mean percentage biomass of high, medium and low palatable species is higher in ungrazed plots. In November, the percentage biomass of only medium palatable species was higher in ungrazed plots and rest of the category is higher in grazed plots. Significant difference in July, a peak growing seasons for most of the plant species in the region reveals that the pasture has impact of livestock grazing. Keywords: Biomass, diversity, grazing effect, rangeland, species Banko Janakari: A journal of forestry information for Nepal Vol.17(1) 2007 pp.25-31


2014 ◽  
Vol 9 (8) ◽  
pp. 777-795
Author(s):  
Andrzej Szczepkowski ◽  
Błażej Gierczyk ◽  
Anna Kujawa

AbstractIn 2010, 16 macrofungi species were found in greenhouses of the Botanical Garden in Warsaw-Powsin. These included 8 species of lepiotaceous fungi and a few species known from warmer areas. For 3 species identified, which are new to Poland (Agaricus subrufescens, Leucocoprinus heinemannii, Marasmius teplicensis), a description is given, with drawings of their microscopic features and photographs. Species composition of macrofungi is compared in 5 complexes of greenhouses (Bayreuth, Graz, Jena, Paskov, Warsaw) in 4 countries from Central Europe. The total number of species in these 5 studies is 206, including 27 (13.2%) lepiotaceous fungi. The smallest number of species identified was in Warsaw (16). More than twice this number was recorded in Jena (33) and Graz (34), while the richest fungal biotas were in Bayreuth (79) and Paskov (88). Of the 16 species found in Warsaw, 8 were also found in other greenhouses. In the group of 33 species recorded in at least two complexes of greenhouses, the most abundant were the lepiotaceous fungi (39.4%) and mycenaceous fungi (15.1%). Leucocoprinus cepistipes and L. straminellus were recorded most often, in 4 of the 5 studied greenhouse complexes. CCA analysis demonstrated that the highest impact on species diversity is the area of greenhouses.


2015 ◽  
Vol 13 (2) ◽  
pp. 105-113
Author(s):  
Gantuya Jargalsaikhan

In a case study, the main objective was to compare three sites with different grazing pressures in Hvitarsida, W-Iceland in relation to current vegetation, seed bank composition and the correlation between those. Our results show that there were significant difference in species composition in above and belowground, giving very little similarity in species composition between seed bank and current vegetation composition. The only exceptions were Agrostis capillaris and Bistorta vivipara that had close similarity between current aboveground vegetation and soil seed bank. Agrostis capillaris had a great abundance in all the sites and Bistorta vivipara proliferates mostly with bulbils that most likely were numerous in the soil. The results of our study agree with current theories on seed bank composition and similar studies,that the similarity between current above ground vegetation and soil seed bank depends on current dominant species (annual or perennial)and the productivity (high or low) of the site.Mongolian Journal of Agricultural Sciences Vol.13(2) 2014: 105-113


Forests ◽  
2019 ◽  
Vol 10 (2) ◽  
pp. 129 ◽  
Author(s):  
Callie Oldfield ◽  
Chris Peterson

Salvage logging after wind disturbance of a mixed conifer-hardwood forest results in sapling compositional changes but no changes to species diversity six years post-disturbance. Several conceptual frameworks allow for predictions of the effects of forest disturbances on composition, but fewer yield predictions of species diversity. Following compound disturbance, tree species diversity and composition is predicted to shift to early successional species. Because of the greater cumulative severity, diversity should be lower in areas experiencing windthrow + salvage logging than in similar sites experiencing windthrow alone. We examined the effects of wind disturbance and salvage logging on diversity parameters over six years. We hypothesized that the effects of salvage logging on diversity would be short-lived, but that species composition would be altered six years post-disturbance. Sampling plots were established in a mixed-hardwood forest in north Georgia, USA, after a 2011 EF3 tornado and surveyed in 2012 and 2017. Nineteen 20 × 20 m plots were surveyed (10 unsalvaged, 9 salvaged) for parameters including Shannon diversity, species richness, and composition. Ordinations were used to visualize tree and sapling species composition in salvage logged plots. We found that there was no significant difference in Shannon diversity between salvaged and unsalvaged plots before disturbance, <1 post-disturbance, or 6 years post-disturbance. The disturbances altered the tree and sapling species compositions, with salvaged plots having more mid-successional saplings but few true pioneer species. There appears to be an emerging pattern in the wind disturbance + salvaging literature which our study supports– salvaging does not affect tree species diversity but shifts species composition over time.


2020 ◽  
Vol 7 (4) ◽  
pp. 192025 ◽  
Author(s):  
Susannah C. Graham ◽  
Alan S. Barrett ◽  
Leslie R. Brown

Mesic Highveld Grassland is important for biodiversity conservation, but is threatened by bush densification from Seriphium plumosum . This indigenous densifier spreads rapidly and outcompetes other herbaceous species, changing the species composition and structure of grasslands. This study looks at three different densities of S. plumosum and how these affect grassland biodiversity within Telperion, Mpumalanga, South Africa. An intermediate density of S. plumosum (1500 individuals (ind) ha −1 ) resulted in the highest plant species diversity ( H = 2.26), a low density (24 ind ha −1 ) was moderately diverse ( H = 1.96) and a high density (9500 ind ha −1 ) was least diverse ( H = 1.78). There were differences between the three densities in terms of plant species diversity, with the intermediate density being significantly more diverse ( p < 0.01) than both the low and high densities. Findings indicate that there was a significant difference between the sites in terms of ecological successional status ( p < 0.01). The presence of S. plumosum at low densities can be considered an integral part of the environment. It is important that in areas where S. plumosum occurs, it should be monitored. If this species is not in balance within its environment and it starts becoming dense, it will negatively affect the biodiversity, species composition and structure of the habitat.


2021 ◽  
Author(s):  
Bernard Eromosele Omomoh ◽  
Victor AJ Adekunle

Abstract BackgroundWe examine the recruitment drive of overstorey and undergrowth of tropical forested reserve by assessing the tree diversity, species composition, species richness, and growth form of the undergrowth on 17 years of post-disturbance. ResultThe result show an increase in the diversity and even distribution of the species of the overstorey, compared to the undergrowth. Conversely, the overstorey has a lower in species richness as compared to the level of undergrowth. One way ANOVA results shows that there is no significant difference (P = 0.341). However, undergrowth density (individual/ha) is found to be significantly (P = 0.000) higher than the overstorey trees.ConclusionsIt is evident that the forest trees and saplings are dissimilar in species abundance, which implies that sapling recruitment is a key determinant of the tree species composition of the forest. It is then concluded that the method adopted for restoration encouraged species diversity in this successional forest.


Author(s):  
Yohannes B. Tesfay ◽  
Juergen Kreyling

Abstract Invasion by exotic species is recognized as one of the major threats to biodiversity. The effects of invasion by Opuntia ficus-indica (Cactaceae) on the species diversity, richness and composition of invaded communities were studied at three sites in the highlands of Eritrea, East Africa. This paper investigates whether the presence of O. ficus-indica causes a negative effect on the native biodiversity in a region rarely studied so far. The vegetation in invaded and uninvaded plots with similar habitat conditions was sampled and differences in the species composition, diversity and richness were compared between the plots. The overall plant species composition differed significantly with invasion by O. ficus-indica. The invasion by O. ficus-indica also led to a significant homogenization of community compositions. The species richness and Shannon diversity index did not differ significantly between the invaded and uninvaded plots. Nevertheless, we still detected species with significantly lower occurrence in the invaded plots (Psiadia punctulata), but also species which preferred invaded plots (Plectranthus hadiensis). We conclude that O. ficus-indica exerts a negligible effect on the species diversity and richness but that it affects species composition and that there are species which suffer due to its presence. Due to the continuous pressure of the invasion by O. ficus-indica on the species composition and dry climates, further homogenization in the native species diversity is to be expected in the future for the highlands of Eritrea.


Author(s):  
Māris Laiviņš ◽  
Gunta Čekstere ◽  
Dārta Kaupe

Abstract At the beginning of the 21st century, in extensively managed mature and over-mature conifer stands (Pinus sylvestris and Picea abies) in Latvia, establishment of native deciduous broad-leaved (Acer platanoides, Tilia cordata, Quercus robur and Ulmus laevis), as well as alien broad-leaved species (Acer pseudoplatanus and Tilia platyphyllos) has been observed. The establishment of deciduous broad-leaved species in coniferous stands is a process known as nemoralisation of coniferous stands, which is characterised by a large number of seedlings of broad-leaved species, young trees and the formation of a subcanopy layer in stands. Based on the age measurements of individuals of broad-leaved species trees, the establishment of some individuals into the studied coniferous stands occurred 40–50 years ago — in the 1970s–1980s. However, the predominant age of alien broad-leaved tree species in the study plots was 15–25 years, i.e. the introduction of large numbers of seedlings of these species in the coniferous stands occurred at the end of the 20th century. In this manner, in the final phase of the conifer replacement process, stable, mostly shade tolerant, mixed stands consisting of 3–4 species have formed, in which spruce is often found together with broad-leaved species.


2020 ◽  
Vol 17 (2) ◽  
pp. 172
Author(s):  
HARMAN AGUSAPUTRA ◽  
MARIA SUGENG ◽  
AYLY SOEKAMTO ◽  
ATIK WULANDARI

<p><strong>Abstract</strong></p><p><strong>Background:</strong> Hydrogen peroxide (H<sub>2</sub>O<sub>2</sub>) as antiseptic has been used frequently to clean woundsin in hospitals and clinics. Hydrogen peroxide has the effectof strong oxidative that can kill pathogens. It can clean up debris and necrotic tissuesin wounds. Hydrogen peroxidealso has hemostatic effect that can help to stop bleeding. Besides antiseptic effects, hydrogen peroxide i s suspected of having negative effect in wound healing. Hydrogen peroxide presumably could cause delayed wound healing by exudate formation and delayed epithelial growth.</p><p><strong>Method</strong>: This study was conducted in the laboratory using 48 white mice that were divided into 2 groups. All the mice were purposely wounded. Afterwards in one group the wounds were clean up using hydrogen peroxide, while in the other group without hydrogen peroxide as control. The wounds of both groups were observed on day 1, day 3 and day 7. On day 1 and day 3, both groups did not show significant difference.</p><p><strong>R</strong><strong>esult</strong> : on day 7 showed that the wound healing in hydrogen peroxide group were delayed. Fifty percent of them had the formation of exudate and 62.5% of them showed delayed epithelial growth.</p><p><strong>Conclusion </strong>: This study could show hydrogen peroxide as wound antiseptic has delayed wound healing effect.</p><p><strong>Keyword</strong>: hydrogen peroxide, wound healing</p>


Sign in / Sign up

Export Citation Format

Share Document