scholarly journals Plant colonization, succession and ecosystem development on Surtsey with reference to neighbouring islands

2014 ◽  
Vol 11 (19) ◽  
pp. 5521-5537 ◽  
Author(s):  
B. Magnússon ◽  
S. H. Magnússon ◽  
E. Ólafsson ◽  
B. D. Sigurdsson
Keyword(s):  
Species Richness ◽  
Plant Biomass ◽  
Vascular Plant ◽  
Plant Cover ◽  
Soil Formation ◽  
Plant Succession ◽  
Permanent Plots ◽  
Plant Colonization ◽  
Nutrient Input ◽  
Species Richness And Diversity

Abstract. Plant colonization and succession on the volcanic island of Surtsey, formed in 1963, have been closely followed. In 2013, a total of 69 vascular plant species had been discovered on the island; of these, 59 were present and 39 had established viable populations. Surtsey had more than twice the species of any of the comparable neighbouring islands, and all of their common species had established on Surtsey. The first colonizers were dispersed by sea, but, after 1985, bird dispersal became the principal pathway with the formation of a seagull colony on the island and consequent site amelioration. This allowed wind-dispersed species to establish after 1990. Since 2007, there has been a net loss of species on the island. A study of plant succession, soil formation and invertebrate communities in permanent plots on Surtsey and on two older neighbouring islands (plants and soil) has revealed that seabirds, through their transfer of nutrients from sea to land, are major drivers of development of these ecosystems. In the area impacted by seagulls, dense grassland swards have developed and plant cover, species richness, diversity, plant biomass and soil carbon become significantly higher than in low-impact areas, which remained relatively barren. A similar difference was found for the invertebrate fauna. After 2000, the vegetation of the oldest part of the seagull colony became increasingly dominated by long-lived, rhizomatous grasses (Festuca, Poa, Leymus) with a decline in species richness and diversity. Old grasslands of the neighbouring islands Elliđaey (puffin colony, high nutrient input) and Heimaey (no seabirds, low nutrient input) contrasted sharply. The puffin grassland of Elliđaey was very dense and species-poor. It was dominated by Festuca and Poa, and very similar to the seagull grassland developing on Surtsey. The Heimaey grassland was significantly higher in species richness and diversity, and had a more even cover of dominants (Festuca/Agrostis/Ranunculus). We forecast that, with continued erosion of Surtsey, loss of habitats and increasing impact from seabirds a lush, species-poor grassland will develop and persist, as on the old neighbouring islands.

scholarly journals Plant colonization, succession and ecosystem development on Surtsey with reference to neighbouring islands

2014 ◽  
Vol 11 (6) ◽  
pp. 9379-9420 ◽  
Author(s):  
B. Magnússon ◽  
S. H. Magnússon ◽  
E. Ólafsson ◽  
B. D. Sigurdsson
Keyword(s):  
Species Richness ◽  
Plant Biomass ◽  
Vascular Plant ◽  
Plant Cover ◽  
Soil Formation ◽  
Plant Succession ◽  
Permanent Plots ◽  
Plant Colonization ◽  
Nutrient Input ◽  
Species Richness And Diversity

Abstract. Plant colonization and succession on Surtsey volcanic island, formed in 1963, have been closely followed. In 2013, a total of 69 vascular plant species had been discovered on the island; of these 59 were present and 39 had established viable populations. Surtsey had more than twice the species of any of the comparable neighbouring islands and all their common species had established on Surtsey. The first colonizers were dispersed by sea, but after 1985 bird-dispersal became the principal pathway with the formation of a seagull colony on the island and consequent site amelioration. This allowed wind-dispersed species to establish after 1990. Since 2007 there has been a net loss of species on the island. A study of plant succession, soil formation and invertebrate communities in permanent plots on Surtsey and on two older neighbouring islands (plants and soil) has revealed that seabirds, through their transfer of nutrients from sea to land, are major drivers of development of these ecosystems. In the area impacted by seagulls dense grassland swards have developed and plant cover, species richness, diversity, plant biomass and soil carbon become significantly higher than in low-impact areas, which remained relatively barren. A similar difference was found for the invertebrate fauna. After 2000, the vegetation of the oldest part of the seagull colony became increasingly dominated by long-lived, rhizomatous grasses (Festuca, Poa, Leymus) with a decline in species richness and diversity. Old grasslands of the neighbouring islands Elliðaey (puffin colony, high nutrient input) and Heimaey (no seabirds, low nutrient input) contrasted sharply. The puffin grassland of Elliðaey was very dense and species-poor. Dominated by Festuca and Poa, it it was very similar to the seagull grassland developing on Surtsey. The Heimaey grassland was significantly higher in species richness and diversity, and had a more even cover of dominants (Festuca/Agrostis/Ranunculus). We forecast that with continued erosion of Surtsey, loss of habitats and increasing impact from seabirds a lush, species poor grassland will develop and persist, as on the old neighbouring islands.

scholarly journals Seabirds and seals as drivers of plant succession on Surtsey

2020 ◽  
Vol 14 ◽  
pp. 115-130
Author(s):  
Borgthór Magnússon ◽  
Gudmundur A. Gudmundsson ◽  
Sigmar Metúsalemsson ◽  
Sandra M. Granquist
Keyword(s):  
Plant Cover ◽  
Plant Succession ◽  
Present Species ◽  
Permanent Plots ◽  
Plant Colonization ◽  
Grey Seal ◽  
Breeding Area ◽  
Vegetation Development ◽  
Dense Patch ◽  
First Time

Plant colonization and succession on Surtsey have been monitored since 1965. In 2019, the 75th species of vascular plants was detected on the island, 62 species were present and about 40 species had established viable populations. Over the last decade colonization has slowed down and the number of present species not increased. The rising number of seagulls breeding on the island after 1985 had a great impact on plant colonization and vegetation development. While most parts of the island remained barren, a grassland area (13 ha in 2018) developed in the main seagull breeding colony on the southern part of the island. This development is attributed to transfer of nutrients from sea to land by the seagulls. In recent years a dense patch of vegetation, 2 ha in 2018, has also developed on the low, northern spit of the island, where a few pairs of seagulls breed in the spring and grey seals haul out and breed in the fall in considerable numbers. In a survey conducted during the grey seal pupping period in 2019, the seal abundance and spatial distribution was mapped accurately for the first time. The results show that the dense vegetation of the spit and seal distribution are clearly overlapping. The continuous shrinking of the island and its spit has led to an increasing concentration of the seals in their breeding area. Based on a literature survey we estimated the nitrogen (N) input from sea to land by the grey seals as 9-13 kg N/ha in 2019. This compares to an estimated input of 5-30 kg N/ha/yr by the seagulls breeding in the same area during 2015-2019. Within the grey seal and seagull breeding area on the spit of the island, a distinct community of shore plants has developed. Measurements of plant cover and biomass in permanent plots on Surtsey in 2018 and 2019 show that development on part of the spit is reaching a similar state as in the old gull colony on the southern part of the island. This suggests that the grey seals along with the seagulls are important drivers of plant succession on the northern spit. Further research on the effects of the seals on nutrient transfer from sea to land and ecosystem development on Surtsey is recommended.

scholarly journals Climate Change Affects Vegetation Differently on Siliceous and Calcareous Summits of the European Alps

2021 ◽  
Vol 9 ◽  
Author(s):  
Lena Nicklas ◽  
Janette Walde ◽  
Sonja Wipf ◽  
Andrea Lamprecht ◽  
Martin Mallaun ◽  
...  
Keyword(s):  
Climate Change ◽  
Species Richness ◽  
Vegetation Change ◽  
Vascular Plant ◽  
Plant Cover ◽  
Permanent Plots ◽  
European Alps ◽  
Climate Data ◽  
Elevation Gradients ◽  
Over Time

The alpine life zone is expected to undergo major changes with ongoing climate change. While an increase of plant species richness on mountain summits has generally been found, competitive displacement may result in the long term. Here, we explore how species richness and surface cover types (vascular plants, litter, bare ground, scree and rock) changed over time on different bedrocks on summits of the European Alps. We focus on how species richness and turnover (new and lost species) depended on the density of existing vegetation, namely vascular plant cover. We analyzed permanent plots (1 m × 1 m) in each cardinal direction on 24 summits (24 × 4 × 4), with always four summits distributed along elevation gradients in each of six regions (three siliceous, three calcareous) across the European Alps. Mean summer temperatures derived from downscaled climate data increased synchronously over the past 30 years in all six regions. During the investigated 14 years, vascular plant cover decreased on siliceous bedrock, coupled with an increase in litter, and it marginally increased on higher calcareous summits. Species richness showed a unimodal relationship with vascular plant cover. Richness increased over time on siliceous bedrock but slightly decreased on calcareous bedrock due to losses in plots with high plant cover. Our analyses suggest contrasting and complex processes on siliceous versus calcareous summits in the European Alps. The unimodal richness-cover relationship and species losses at high plant cover suggest competition as a driver for vegetation change on alpine summits.

scholarly journals Changes in plant diversity in a water-limited and isolated high-mountain range (Sierra Nevada, Spain)

Alpine Botany ◽  
2021 ◽  
Author(s):  
Andrea Lamprecht ◽  
Harald Pauli ◽  
Maria Rosa Fernández Calzado ◽  
Juan Lorite ◽  
Joaquín Molero Mesa ◽  
...  
Keyword(s):  
Species Richness ◽  
Snow Cover ◽  
Sierra Nevada ◽  
Plant Diversity ◽  
Endemic Species ◽  
Vascular Plant ◽  
Climate Change Impacts ◽  
Permanent Plots ◽  
High Mountain ◽  
Mountain Range

AbstractClimate change impacts are of a particular concern in small mountain ranges, where cold-adapted plant species have their optimum zone in the upper bioclimatic belts. This is commonly the case in Mediterranean mountains, which often harbour high numbers of endemic species, enhancing the risk of biodiversity losses. This study deals with shifts in vascular plant diversity in the upper zones of the Sierra Nevada, Spain, in relation with climatic parameters during the past two decades. We used vegetation data from permanent plots of three surveys of two GLORIA study regions, spanning a period of 18 years (2001–2019); ERA5 temperature and precipitation data; and snow cover durations, derived from on-site soil temperature data. Relationships between diversity patterns and climate factors were analysed using GLMMs. Species richness showed a decline between 2001 and 2008, and increased thereafter. Species cover increased slightly but significantly, although not for endemic species. While endemics underwent cover losses proportional to non-endemics, more widespread shrub species increased. Precipitation tended to increase during the last decade, after a downward trend since 1960. Precipitation was positively related to species richness, colonisation events, and cover, and negatively to disappearance events. Longer snow cover duration and rising temperatures were also related to increasing species numbers, but not to cover changes. The rapid biotic responses of Mediterranean alpine plants indicate a tight synchronisation with climate fluctuations, especially with water availability. Thus, it rather confirms concerns about biodiversity losses, if projections of increasing temperature in combination with decreasing precipitation hold true.

scholarly journals Composition and Diversity of Areas Under Restoration Process From the Brazilian Atlantic Forest

2019 ◽  
Vol 11 (9) ◽  
pp. 154
Author(s):  
Marília Isabelle Oliveira da Silva ◽  
Luiz Carlos Marangon ◽  
Ana Lícia Patriota Feliciano ◽  
Marilia Alves Grugiki
Keyword(s):  
Species Richness ◽  
Atlantic Forest ◽  
Environmental Sustainability ◽  
Forest Restoration ◽  
Permanent Plots ◽  
Brazilian Atlantic Forest ◽  
Forest Fragment ◽  
Restoration Process ◽  
Species Richness And Diversity ◽  
Reference Ecosystem

The evaluation of the forest restoration scenario is of great importance, with floristic composition and diversity being among the most used ecological variables as indicators. This research aimed to identify the current situation, in terms of species composition and diversity, of two riparian forests under restoration based on a reference ecosystem, the Brazilian Atlantic Forest. Twenty permanent plots (250 m²) were located in areas under restoration process (AR1 and AR2) and in a forest fragment of the region which served as a reference ecosystem (ER). We sampled, identified and classified all tree individuals with CBH ≥ 15.0 cm in each plot. Aiming to understand species richness and diversity, besides the traditional indexes (Shannon and Simpson), we also estimated the effective numbers of Hill’s diversity (qD = 0, 1 and 2) considering rarefaction (P ≤ 0.05); and to detect floristic similarities among the study areas we performed a Principal Coordinate Analysis (PCoA). We found dissimilarity among ARs and ER, and the presence of exotic species, indicating that, as recommended, such reference should have been taken into account during the planning of the restoration action. Considering the effective numbers of species (qD) we found differences between the areas, species richness and diversity was higher in ER > AR2 > AR1. We also show that among the restoration areas, with the same age and submitted to the same conditions, AR2 has features that allow us to conclude that this area has a bigger chance of success in the restoration process. However, aiming environmental sustainability, we suggest that some corrective actions should be taken in order to favour the reestablishment of ecological processes in these areas.

scholarly journals Floodplain succession pattern along Budhi-Rapti River bank, Chitwan, Nepal

2018 ◽  
Vol 11 ◽  
pp. 12-26
Author(s):  
Dhiraj Chhetri Kunwar ◽  
Chitra Bahadur Baniya
Keyword(s):  
Species Richness ◽  
Vascular Plant ◽  
Significant Negative Correlation ◽  
Initial Position ◽  
Plant Succession ◽  
Systematic Sampling ◽  
Ageratum Conyzoides ◽  
River Bank ◽  
Total Species Richness ◽  
Time Substitution

 Riverine floodplain is one of the most productive lowland ecosystems in Nepal. However, floodplain ecology is less understood due to its fluctuation. Budhi-Rapti River in Chitwan, central Nepal formed a floodplain along the Khorsor zone of Barandabhar corridor. This study was carried out to understand the floodplain ecosystem development after plant succession. The space for time substitution method of vegetation sampling was adopted in order to sample the floodplain created at different chronosequence. The floodplain that lies perpendicular to and 200 m away from the Budhi-Rapti river was sampled. Systematic sampling was done along two parallel transects, almost 200 m apart from each other. Sampling along the transect started right after 200 m away from the Budhi-River bank. Initial position of these transects towards Budhi-Rapti river was believed to be the youngest floodplain, which slowly getting older after passing away from the river. Abundance of vascular plant species was recorded in sample plots of 20 × 20 m each subdivided equally into 4 subplots (each of 100 m2). Along each transect, vegetation data was recorded from a series of 20 plots, placed 50 m apart from each other. Successional scores were calculated and utilized as environmental variables after applying non-metric multi-dimensional scaling (NMDS) through metaMDS. Total and life form (herbs, shrubs and trees) richness patterns were calculated. Altogether, 158 species of vascular plants under 60 families and 136 genera were recorded. Gramineae was the richest family followed by Leguminosae, Asteraceae and Cyperaceae. Total species richness showed significant negative correlation with the NMDS1 and NMDS2, which justified a convergent pattern of succession. Herb, orchid and shrub species richness also showed significant declining pattern with NMDS1. Persicaria barbata, Parthenium hysterophorus, Ageratum conyzoides and Typha angustifolia were early succession indicator species; whereas Albizia lucidior, Miliusa velutina, Ficus hispida, Bauhinia purpurea and Brassaiopsis glomerulata were the late succession tree species. This study agreed with the convergent model of succession.Botanica Orientalis – Journal of Plant Science (2017) 11: 12–26

scholarly journals Effects of Cattle on the Abundance and Composition of Carabid Beetles in Temperate Grasslands

2014 ◽  
Vol 3 (1) ◽  
pp. 36
Author(s):  
Eleanor R. L. Bassett ◽  
Lauchlan H Fraser
Keyword(s):  
Species Richness ◽  
Plant Biomass ◽  
Cattle Grazing ◽  
Carabid Beetles ◽  
Plant Structure ◽  
Site Productivity ◽  
Insect Communities ◽  
Species Richness And Diversity ◽  
Natural Grasslands ◽  
High Site

Grasslands are of vital importance to the ranching industry. Cattle grazing can alter the structure and composition of the plant community, and may indirectly affect insect communities. We investigated the effects of cattle grazing and site productivity on carabid beetle abundance, dried weight (biomass), species richness and diversity. We used pitfall traps to capture beetles in three sessions in 2008 in Lac Du Bois Provincial Park, British Columbia (B.C.), Canada. To test for main and interacting effects of elevation and grazing, carabid beetles were quantified by trap for abundance, dried weight (biomass), species richness and Shannon’s diversity. We found that elevation (a proxy of site productivity) was the most important predictor of carabid parameters, with lower elevation (low site productivity) having lower abundance, biomass, species richness and diversity compared to upper elevation (high site productivity). Although there was no main effect caused by grazing, there was a reduction in carabid biomass and diversity at grazed upper elevation sites compared to ungrazed upper elevation sites, suggesting that site productivity and plant structure affects carabid communities. Cattle management of natural grasslands benefits by considering biodiversity of all biota, including invertebrates. Carabid species diversity can be maximized by restricting grazing at high site productivity where plant biomass and litter is high.

scholarly journals Impact of land-use change in mountain semi-dry meadows on plants, litter decomposition and earthworms

Web Ecology ◽  
2019 ◽  
Vol 19 (2) ◽  
pp. 53-63 ◽  
Author(s):  
Ines Jernej ◽  
Andreas Bohner ◽  
Ronnie Walcher ◽  
Raja Imran Hussain ◽  
Arne Arnberger ◽  
...  
Keyword(s):  
Species Richness ◽  
Litter Decomposition ◽  
Plant Species ◽  
Plant Traits ◽  
Plant Biomass ◽  
Plant Cover ◽  
Higher Plant ◽  
Study Region ◽  
Earthworm Species ◽  
Tea Bag Index

Abstract. Traditionally managed mountain grasslands are biodiversity hotspots in central Europe. However, socio-economic trends in agriculture during the last decades have changed farming practices, leaving steep and remote sites abandoned. Especially the abandonment of meadows is well known to directly affect plant and insect diversity. However, not much is known about the effects on soil processes and soil biota. To assess this, we studied four extensively managed (mown once a year, no fertilization) and four abandoned (no mowing, no fertilization) semi-dry meadows in a mountain region in Austria. Plant species richness, plant cover, plant traits, plant biomass, litter decomposition (tea bag index), and earthworm species richness and density were assessed. Additionally, soil temperature, moisture and electrical conductivity were measured. Results showed that managed meadows contained more plant species than abandoned meadows (118 vs. 93 species, respectively). We also observed different plant species assemblages between the two management types. In managed meadows, hemirosette and ruderal plant species were more abundant, while more plant species without rosettes and a higher plant necromass were found in abandoned meadows. Additionally, decomposition rate was higher in abandoned meadows. There was a trend towards higher earthworm densities in managed meadows, but there was no difference in earthworm species richness. We conclude that meadow management has effects on both aboveground vegetation and belowground biota and processes. Both abandoned and extensively managed meadows were important to sustain overall biodiversity and ecosystem functioning in the study region.

Is there a middle way between permanent plots and chronosequences?

2008 ◽  
Vol 38 (12) ◽  
pp. 3133-3138 ◽  
Author(s):  
Randall W. Myster ◽  
Michael P. Malahy
Keyword(s):  
Species Richness ◽  
Structural Parameters ◽  
Plant Cover ◽  
Permanent Plots ◽  
Vegetation Changes ◽  
Middle Way ◽  
Total Species Richness ◽  
Luquillo Mountains ◽  
Total Plant ◽  
Total Species

Although permanent plots have proven critical to studies of vegetation dynamics, their logistic limitations have led to the wide use of chronosequences as an alternative. Here, we test whether or not an approach combining permanent plots and chronosequences could be used successfully to accurately predict the vegetation changes that one would see in permanent plots in the same area. We used plot data from five pastures in the Luquillo Mountains of Puerto Rico, USA, and found that (i) for species composition and abundance, the five pastures did not form a single trajectory or show any convergence, (ii) for successional rate, there was a general decrease with time since abandonment for most pastures, but that decrease was not monotonic and one pasture of the five had no decrease at all, and (iii) total species richness and total plant cover showed pastures that lined up well by age, forming almost a single trajectory with little variation. We conclude that the utility of using chronosequences either alone or with permanent plots depends largely on the parameter under study with broad structural parameters, such as total species richness and total plant cover, performing best.

scholarly journals Spectral Diversity Metrics for Detecting Oil Pollution Effects on Biodiversity in the Niger Delta

2019 ◽  
Vol 11 (22) ◽  
pp. 2662 ◽  
Author(s):  
Nkeiruka Onyia ◽  
Heiko Balzter ◽  
Juan Berrio
Keyword(s):  
Species Richness ◽  
Niger Delta ◽  
Oil Pollution ◽  
Vascular Plant ◽  
Vegetation Indices ◽  
P Value ◽  
Biodiversity Monitoring ◽  
Species Richness And Diversity ◽  
Vegetation Characteristics ◽  
Diversity Metrics

Biodiversity monitoring in the Niger delta has become pertinent in view of the incessant spillages from oil production activities and the socio-economic impact of these spillages on the inhabitants who depend on the resources for their livelihood. Conventional methods of post-impact assessments are expensive, time consuming, and cause damage to the environment, as they often require the removal of affected samples/specimens for laboratory analysis. Remote sensing offers the opportunity to track biodiversity changes from space while using the spectral variability hypothesis (SVH). The SVH proposes that the species diversity of a sampled area is linearly correlated with the variability of spectral reflectance of the area. Several authors have tested the SVH on various land cover types and spatial scales; however, the present study evaluated the validity of the SVH against the backdrop of oil pollution impact on biodiversity while using vascular plant species as surrogates. Species richness and diversity indices were computed from vegetation data collected from polluted and non-polluted transects. Spectral metrics that were derived from Sentinel 2 bands and broadband vegetation indices (BVIs) using various algorithms, including averages, spread, dimension reduction, and so on, were assessed for their ability to estimate vascular plants species richness and diversity. The results showed significant differences in vegetation characteristics of polluted and control transects (H = 76.05, p-value = <0.05 for abundance and H = 170.03, p-value < 0.05 for richness). Spectral diversity metrics correlated negatively with species data on polluted transects and positively on control transects. The metrics computed using Sentinel 2A bands and vegetation indices proved to be sensitive to changes in vegetation characteristics following oil pollution. The most robust relationship was observed between the metrics and indices on control transects, whereas the weakest relationships were observed on polluted transects. Index-wise, the Simpson’s diversity index regressed better with spectral metrics (R2 > 0.5), whereas the Chao-1 richness index regressed the least (R2 < 0.5). The strength of the relationship resulted in successfully estimating species richness and diversity values of investigated transects, thereby enhancing biodiversity monitoring over time and space.

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