scholarly journals Invasive Melastomataceae in Seychelles

Oryx ◽  
1993 ◽  
Vol 27 (1) ◽  
pp. 22-26 ◽  
Author(s):  
Justin Gerlach
Keyword(s):  
Plant Species ◽  
Oceanic Islands ◽  
Natural Forest ◽  
Native Vegetation ◽  
Native Forest ◽  
Introduced Plant Species

The Seychelles are the only high oceanic islands of granitic origin and their native vegetation is thus of considerable botanical interest. In the nineteenth and early twentieth centuries widespread clearance for coconut and cinnamon plantations resulted in native forest being confined mainly to montane areas. Cinnamon has proved to be very invasive in natural forest and a number of other introduced plant species have also been recognized as problematic for some time. Recent studies have revealed that two more introduced plant species - Memecylon floribunda and Clidemia hirta - are significant new threats to native vegetation on Mahe and Silhouette, respectively.

scholarly journals Effect of exotic tree plantation on floristic composition and phytodiversity of Rema-Kalenga wildlife sanctuary, Bangladesh

2016 ◽  
Vol 3 (2) ◽  
pp. 33-47
Author(s):  
Gazi Mosharof Hossain ◽  
ABM Enayet Hossain
Keyword(s):  
Plant Species ◽  
Negative Impact ◽  
Diversity Index ◽  
Vascular Plant ◽  
Floristic Composition ◽  
Natural Forest ◽  
Wildlife Sanctuary ◽  
Tree Plantation ◽  
Exotic Tree ◽  
Index Value

Effect of exotic tree plantation on floristic composition and phytodiversity status of Rema-Kalenga wildlife sanctuary of Bangladesh was studied. A total of 309 vascular plant species under 245 genera belonging to 83 families were found to constitute the vascular flora of the studied area. The maximum number of species (298) with the highest Shannon-Weiner diversity index value (3.882±0.090) was recorded from natural forest, which was followed by 194 and 165 plant species with 3.441±0.205 and 3.398±0.103 diversity index values recorded from Tectona and Acacia plantation sites respectively. The minimum number of plant species (142) with the lowest diversity index value (2.999±0.152) was recorded from Eucalyptus plantation site. The collected data on the selected forest sites of Rema-Kalenga wildlife sanctuary showed the trends of gradual decrease in floristic composition and phytodivesity status of three plantation sites (Tectona to Acacia to Eucalyptus) in respect to natural forest, which indicated that exotic tree plantations might have negative impact on floristic composition and phytodiversity of this semi-tropical forest area and the fast-growing exotic tree plantation of Acacia and Eucalyptus should be avoided for sustainable development of Rema-Kalenga wildlife sanctuary.Jahangirnagar University J. Biol. Sci. 3(2): 33-47, 2014 (December)

scholarly journals Effects of land cover type on carabid beetles (Coleoptera: Carabidae) of the Canterbury foothills, New Zealand

2019 ◽  
Vol 49 ◽  
Author(s):  
Lisa A. Berndt ◽  
Eckehard G. Brockerhoff
Keyword(s):  
New Zealand ◽  
Land Cover ◽  
Natural Forest ◽  
Carabid Beetle ◽  
Carabid Beetles ◽  
Native Forest ◽  
Potential Contribution ◽  
Pine Plantation ◽  
Plantation Forest ◽  
Beetle Assemblages

Background: Land cover changes during the recent history of New Zealand have had a major impact on its largely endemic and iconic biodiversity. As in many other countries, large areas of native forest have been replaced by other land cover and are now in exotic pasture grassland or plantation forest. Ground beetles (Carabidae) are often used as ecological indicators, they provide ecosystem services such as pest control, and some species are endangered. However, few studies in New Zealand have assessed the habitat value for carabid beetles of natural forest, managed regenerating natural forest, pine plantation forest and pasture. Methods: We compared the carabid beetle assemblages of natural forest of Nothofagus solandri var solandri (also known as Fuscospora solandri or black beech), regenerating N. solandri forest managed for timber production, exotic pine plantation forest and exotic pasture, using pitfall traps. The study was conducted at Woodside Forest in the foothills of the Southern Alps, North Canterbury, New Zealand, close to an area where the critically endangered carabid Holcaspis brevicula was found. Results: A total of 1192 carabid individuals from 23 species were caught during the study. All but two species were native to New Zealand, with the exotic species present only in low numbers and one of these only in the pasture habitat. Carabid relative abundance and the number of species was highest in the pine plantation, where a total of 15 species were caught; however, rarefied species richness did not differ significantly between habitats. The sampled carabid beetle assemblages were similar across the three forested habitat types but differed significantly from the pasture assemblages based on unconstrained and canonical analyses of principal coordinates. Holcaspis brevicula was not detected in this area. Conclusions: Our results show that managed or exotic habitats may provide habitat to species-rich carabid assemblages although some native species occur only in natural, undisturbed vegetation. Nevertheless, it is important to acknowledge the potential contribution of these land uses and land cover types to the conservation of native biodiversity and to consider how these can be managed to maximise conservation opportunities.

scholarly journals At a Microsite Scale, Native Vegetation Determines Spatial Patterns and Survival of Pinus contorta Invasion in Patagonia

Forests ◽  
2019 ◽  
Vol 10 (8) ◽  
pp. 654 ◽  
Author(s):  
Bárbara Langdon ◽  
Lohengrin A. Cavieres ◽  
Aníbal Pauchard
Keyword(s):  
Plant Species ◽  
Pinus Contorta ◽  
Point Pattern Analysis ◽  
Point Pattern ◽  
Native Vegetation ◽  
Native Plant ◽  
Patagonian Steppe ◽  
Stressful Environment ◽  
Management Actions ◽  
Tussock Grasses

Research Highlights: The invasive species Pinus contorta, has become a new component of the vegetation in the Patagonian Steppe, invading the complex matrix of bare ground, tussock grasses and cushion plants. At a microsite scale, the type of native vegetation is one of the multiple factors determining the establishment of P. contorta and in some cases, increasing its survival, and as a result, the invasion of the species. Background and Objectives: The presence of trees, particularly pines, where they are naturally absent, represents a clear threat to Patagonian steppe ecosystems. Thus, understanding the interaction between pines and native plant species may be the key to understanding the invasion and applying management actions. Pinus contorta is considered one of the most aggressive among the pines species, with recognized impacts on regions in the southern hemisphere and Europe, and it is one of the main invaders in the Patagonian steppe. Our aim in this study is to determine the influence of surrounding vegetation on P. contorta spatial distribution, its establishment and future development in the Chilean Patagonia. Materials and Methods: We used point pattern analysis to determine the existence of spatial associations between P. contorta and the resident vegetation of the Patagonian steppe. Further, a seeding experiment was carried out to assess the influence of the surrounding vegetation during P. contorta establishment and first growing season. Results: We found that young P. contorta individuals are positively associated with the native cushion plant B. magellanica and also to tussock grasses. Seeding experiments showed that P. contorta is influenced by resident plant species during establishment and is able to establish on any ground cover type in the Patagonian steppe, but some resident plant species increase P. contorta survival chances. Conclusions: Pinus contorta is interacting with native vegetation and becoming an active component of the Patagonian steppe mosaic. Although pines can establish in any type of vegetation in the Patagonian steppe mosaics, native cushion and tussock grasses may be facilitating the process and promoting pine survival, allowing it to survive and thrive in this stressful environment.

Impacts of erosion control treatments on native vegetation recovery after severe wildfire in the Eastern Cascades, USA

2010 ◽  
Vol 19 (4) ◽  
pp. 490 ◽  
Author(s):  
Erich K. Dodson ◽  
David W. Peterson ◽  
Richy J. Harrod
Keyword(s):  
Species Richness ◽  
Plant Species ◽  
Native Species ◽  
Plant Cover ◽  
Plant Species Richness ◽  
Tree Regeneration ◽  
Vegetation Recovery ◽  
Native Vegetation ◽  
Individual Plant ◽  
Native Plant

Slope stabilisation treatments like mulching and seeding are used to increase soil cover and reduce runoff and erosion following severe wildfires, but may also retard native vegetation recovery. We evaluated the effects of seeding and fertilisation on the cover and richness of native and exotic plants and on individual plant species following the 2004 Pot Peak wildfire in Washington State, USA. We applied four seeding and three fertilisation treatments to experimental plots at eight burned sites in spring 2005 and surveyed vegetation during the first two growing seasons after fire. Seeding significantly reduced native non-seeded species richness and cover by the second year. Fertilisation increased native plant cover in both years, but did not affect plant species richness. Seeding and fertilisation significantly increased exotic cover, especially when applied in combination. However, exotic cover and richness were low and treatment effects were greatest in the first year. Seeding suppressed several native plant species, especially disturbance-adapted forbs. Fertilisation, in contrast, favoured several native understorey plant species but reduced tree regeneration. Seeding, even with native species, appears to interfere with the natural recovery of native vegetation whereas fertilisation increases total plant cover, primarily by facilitating native vegetation recovery.

scholarly journals Interpretation of patterns of genetic variation in endemic plant species of oceanic islands

2013 ◽  
Vol 174 (3) ◽  
pp. 276-288 ◽  
Author(s):  
Tod F. Stuessy ◽  
Koji Takayama ◽  
Patricio López-Sepúlveda ◽  
Daniel J. Crawford
Keyword(s):  
Genetic Variation ◽  
Plant Species ◽  
Oceanic Islands ◽  
Endemic Plant ◽  
Endemic Plant Species

scholarly journals Comparing Negative Impacts of Prunus serotina, Quercus rubra and Robinia pseudoacacia on Native Forest Ecosystems

Forests ◽  
2019 ◽  
Vol 10 (10) ◽  
pp. 842 ◽  
Author(s):  
Gentili ◽  
Ferrè ◽  
Cardarelli ◽  
Montagnani ◽  
Bogliani ◽  
...  
Keyword(s):  
Invasive Species ◽  
Plant Species ◽  
Forest Ecosystems ◽  
Quercus Rubra ◽  
Robinia Pseudoacacia ◽  
Prunus Serotina ◽  
Native Forest ◽  
Alien Plant Species ◽  
Alien Plant ◽  
Negative Impacts

The introduction of invasive alien plant species (IAPS) can modify plant-soil feedback, resulting in an alteration of the abiotic and biotic characteristics of ecosystems. Prunus serotina, Quercus rubra and Robinia pseudoacacia are IAPS of European temperate forests, where they can become dominant and suppress the native biodiversity. Assuming that the establishment of these invasive species may alter native forest ecosystems, this study comparatively assessed their impact on ecosystems. This study further investigated plant communities in 12 forest stands, dominated by the three IAPS and native trees, Quercus robur and Carpinus betulus (three plots per forest type), in Northern Italy, and collected soil samples. The relationships between the invasion of the three IAPS and modifications of humus forms, soil chemical properties, soil biological quality, bacterial activity and plant community structure and diversity (α-, β-, and γ-diversity) were assessed using one-way ANOVA and redundancy analyses (RDA). Our comparative study demonstrated that invaded forests often had unique plant and/or soil properties, relative to native forests, and the degree of dissimilarity depended on the invasive species. Particularly, Q. rubra is related to major negative impacts on soil organic horizons and low/modified levels of microarthropod and plant biodiversity. R. pseudoacacia is associated with an altered base content of soil and, in turn, with positive feedback to the soil biological quality (QBS-ar) and plant diversity, but with a high cover compared with other alien plant species. P. serotina is associated with intermediate impacts and exhibits a plant species assemblage that is more similar to those of native forest stands. Our work suggests impact-based management decisions for the three investigated IAPS, since their effects on the diversity and composition of resident ecosystems are very different.

scholarly journals Microclimate determines community composition but not richness of epiphytic understory bryophytes of rainforest and cacao agroforests in Indonesia

2009 ◽  
Vol 36 (2) ◽  
pp. 171 ◽  
Author(s):  
S. Goda Sporn ◽  
Merijn M. Bos ◽  
Monika Hoffstätter-Müncheberg ◽  
Michael Kessler ◽  
S. Robbert Gradstein
Keyword(s):  
Species Richness ◽  
Species Composition ◽  
Community Composition ◽  
Natural Forest ◽  
Native Forest ◽  
Shade Trees ◽  
Natural Forests ◽  
High Turnover ◽  
Forest Flora ◽  
Understory Trees

Management intensification in cultivated, tropical forests drives changes in the microclimate that can threaten native forest flora and fauna. In this study, we use epiphytic bryophytes, known to be sensitive to microclimatic changes due to their lack of a protective cuticle and the exposed habitat, to investigate the predictive power of microclimate for changes in species richness and composition. Bryophytes were sampled from understory trees in natural forest and cacao (Theobroma cacao L.) trees in two types of cacao agroforests (natural shade trees and planted shade trees) in Central Sulawesi, Indonesia. The microclimate in the agroforests was characterised by low air humidity and high air temperature during the afternoon. Bryophyte species richness did not differ between habitat types but species composition changed markedly from the natural forest to the cacao agroforests. Although no correlation between species richness and microclimate values could be found, a series of matrix-based analyses revealed a significantly positive relationship between similarities in species composition and in maximum values for temperature and minimum values for humidity, which suggests that microclimatic changes are a good predictor for high turnover of bryophyte community composition from natural forests to cacao agroforests.

scholarly journals Ant recolonization of rehabilitated bauxite mines at Trombetas, Pará, Brazil

1996 ◽  
Vol 12 (2) ◽  
pp. 257-273 ◽  
Author(s):  
Jonathan D. Majer
Keyword(s):  
Full Range ◽  
Single Species ◽  
Forest Tree ◽  
Rate Of Return ◽  
Habitat Requirements ◽  
Native Vegetation ◽  
Native Forest ◽  
Generalist Species ◽  
Ant Community ◽  
Bauxite Mines

ABSTRACTAnt species were sampled in three rainforest and 10 rehabilitated bauxite mine plots at Trombetas, in the tropical monsoonal region of Brazil. Rehabilitation ranged from 0 to 11 years in age and was mainly performed by planting mixed native forest tree species. One plot supported single-species blocks of Australian Eucalyptus and Acacia species. Two hundred and six ant species were recorded, of which 82 were exclusively found in the native vegetation, 54 were confined to the rehabilitation and 70 were found in both situations. In contrast with other studies, ant species richness in the Eucalyptus/Acacia plantation was as great as in the areas rehabilitated with native vegetation. The overall rate of return of ant species was considerably greater than in mines situated within subtropical regions of Brazil, Africa and Australia. However, if the greater richness of ants in the native vegetation at Trombetas was accounted for, the proportional return of the original ant fauna was not particularly rapid. The return of ant species slowed as the rehabilitated areas aged. In comparison with forest, the rehabilitation was characterized by proportionately more generalist species and fewer specialists, especially from the soil and litter layers. The full range of habitat requirements for the ant community has not been restored by the eleventh year of rehabilitation and further management may be required to enhance the degree of colonization. It is suggested that the findings for ants may apply to other components of the biota as well.

Nitrification potential in the rhizosphere of Australian native vegetation

Soil Research ◽  
2017 ◽  
Vol 55 (1) ◽  
pp. 58 ◽  
Author(s):  
Saikat Chowdhury ◽  
Ramya Thangarajan ◽  
Nanthi Bolan ◽  
Julianne O'Reilly-Wapstra ◽  
Anitha Kunhikrishnan ◽  
...  
Keyword(s):  
Plant Growth ◽  
Microbial Activity ◽  
Plant Species ◽  
Native Plants ◽  
Rhizosphere Soil ◽  
Native Vegetation ◽  
Rhizosphere Soils ◽  
Nitrification Potential ◽  
Growth Experiments ◽  
Australian Native Plants

The rhizosphere influences nutrient dynamics in soil mainly by altering microbial activity. The objective of this study was to evaluate the rhizosphere effect on nitrogen transformation in Australian native vegetation in relation to nitrification potential (NP). Microbial activity, NP, and nitrifiers (ammonia-oxidising bacteria, AOB) were compared between rhizosphere and non-rhizosphere soils of several Australian native vegetation under field conditions. These parameters were also measured with increasing distance from the rhizosphere of selected plant species using plant growth experiments. To examine the persistence of nitrification inhibitory activity of rhizosphere soil on non-rhizosphere soil, the soils were mixed at various ratios and examined for NP and AOB populations. The rhizosphere soil from all native vegetation (29 species) had higher microbial activity than non-rhizosphere soil, whereas 13 species showed very low NP in the rhizosphere when compared with non-rhizosphere soil. Nitrification potential and AOB populations obtained in the soil mixture were lower than the predicted values, indicating the persistence of a nitrification inhibitory effect of the rhizosphere soils on non-rhizosphere soils. In plant growth experiments the microbial activity decreased with increasing distance from rhizosphere, whereas the opposite was observed for NP and AOB populations, indicating the selective inhibition of nitrification process in the rhizosphere of the Australian native plants Scaevola albida, Chrysocephalum semipapposum, and Enteropogon acicularis. Some Australian native plants inhibited nitrification in their rhizosphere. We propose future studies on these selected plant species by identifying and characterising the nitrification inhibiting compounds and also the potential of nitrification inhibition in reducing nitrogen losses through nitrate leaching and nitrous oxide emission.

scholarly journals Effects of Exotic Plantation Expansion and Management Intervention on Woody Plant Species Diversity, Regeneration and Soil Seed Bank in Tarmaber District, Ethiopia

2021 ◽  
Author(s):  
Melese Bekele Nigussie ◽  
Dessie Assefa Assefa ◽  
Yohannis Gebremariam Gebremariam
Keyword(s):  
Species Diversity ◽  
Plant Species ◽  
Seed Bank ◽  
Woody Plant ◽  
Soil Seed Bank ◽  
Natural Forest ◽  
Forest Types ◽  
Plantation Forest ◽  
Woody Plant Species ◽  
Management Intervention

Abstract This study was carried out in Tarmaber district north shewa zone Ethiopia to determine the effect of plantation forest with management intervention on woody plant species diversity, regeneration and soil seed bank species composition in five different forest types, which are adjacent natural forest, managed Cupressus lusitanica, unmanaged C. lusitanica, managed Eucalyptus globules and not managed E. globules plantation forests. A total of 75 circular sample plots of 314 m2 were established along a transect lines. Soil seed bank analysis was done from soil samples collected in each of the plots (225 samples) to examine the similarity between the soil seed bank and aboveground flora. Different diversity index and ANOVA was used in SPSS software for analysis. The result showed that a total of 51 woody plant species was recorded in adjacent natural forest (41), managed C. lusitanica (27), not managed C. lusitanica (9), managed E. globules (22) and not managed E. globules (13) species. Regeneration of seedlings were 3538, 5567, 707, 1462 and 2524 mean stems ha− 1 for natural forest, managed C. lusitanica, not managed C. lusitanica, managed E. globules and not managed E. globules respectively. Unmanaged C. lusitanica plantations had significantly lower densities of mature tree stems ha− 1 as compared to managed C. lusitanica, managed E. globules and adjacent natural forest (F = 14.03, p < 0.05).Similarly in terms of sapling density ha− 1 unmanaged C. lusitanica was significantly lower from other forest types (F = 7.37, p < 0.05). However managed C. lusitanica had significantly higher seedling regeneration (stem density ha− 1) than other plantation and adjacent natural forests (F = 16.11, p < 0.05). Generally mean stem densities including tree, sapling and seedling of woody species among different forest types managed C. lusitanica was significantly higher among different forest types (F = 13.01, p < 0.05). From the soil seed bank a total of 22 plant species (20 native and 2 exotic) species were recovered. In different forest types the number of species recorded was in adjacent natural forest (19), managed C. lusitanica (11), unmanaged C. lusitanica (4), managed E. globules (7) and unmanaged E. globules (5). The similarity of the oil seed bank was more or less similar to the above ground flora with maximum Sorenson’s similarity values of 0.633. Generally with appropriate management intervention undergrowth vegetation and soil seed bank status in plantation forest had good species composition and diversity.

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