Are regional ecosystems compatible with floristic heterogeneity? A case study from Toohey Forest, south-east Queensland, Australia

2007 ◽  
Vol 13 (1) ◽  
pp. 47 ◽  
Author(s):  
Grant W. Wardell-Johnson ◽  
Ben E. Lawson ◽  
Robert H. Coutts
Keyword(s):  
Species Richness ◽  
Environmental Variables ◽  
A Priori ◽  
Vascular Plant ◽  
Vegetation Mapping ◽  
Heterogeneous Environments ◽  
Several Variables ◽  
Total Species Richness ◽  
Corymbia Citriodora ◽  
Mapping Scale

The recognition and effective portrayal of floristic heterogeneity is a complex issue for land classification. This study in Toohey Forest, south-east Queensland, examines the effects of mapping scale and environmental variables on a floristically heterogeneous area. Current Version 4.1 regional ecosystem mapping at 1: 1 00 000 scale maps Toohey Forest as a single regional ecosystem unit "12.11.5", described as an "open forest complex with Corymbia citriodora, Eucalyptus siderophloia, E. major on metamorphics ± interbedded volcanics". Plant taxa data from 50, 20 x 20 m sites comprising 247 native vascular plant taxa were collected, along with data for 17 environmental variables and 10 species richness categories. A priori site groupings of 1 :12 500 scale vegetation mapping and a geomorphic classifications of the area were examined using cluster analysis (UPGMA, Bray-Curtis Metric, β = –0.1) and ordination (SSH MDS). Biplots of several variables (shrub species richness, total species richness, per cent rock cover, CEC, carbon and phosphorus) were significantly (P < 0.05) correlated with the ordination axes derived from each of the two strata levels and the total taxa, for both geomorphological and vegetation mapping. Several variables (shrub, vine, woody and introduced species richness, and carbon, nitrogen, phosphorus, pH and CEC) varied significantly (P < 0.05) across both geomorphic categories and 1:12 500 scale vegetation community mapping. The ongoing reduction in regional ecosystem mapping scale, centred on the use of fine-scale geomorphology mapping, is likely to improve the representation of floristic patterns in heterogeneous environments.

scholarly journals Altitudinal Vascular Plant Richness and Climate Change in the Alpine Zone of the Lefka Ori, Crete

Diversity ◽  
2021 ◽  
Vol 13 (1) ◽  
pp. 22
Author(s):  
George Kazakis ◽  
Dany Ghosn ◽  
Ilektra Remoundou ◽  
Panagiotis Nyktas ◽  
Michael A. Talias ◽  
...  
Keyword(s):  
Climate Change ◽  
Species Richness ◽  
Spatial Scales ◽  
Vascular Plant ◽  
Monitoring Network ◽  
Mediterranean Area ◽  
Mean Annual Temperature ◽  
High Mountain ◽  
Species Loss ◽  
Total Species Richness

High mountain zones in the Mediterranean area are considered more vulnerable in comparison to lower altitudes zones. Lefka Ori massif, a global biodiversity hotspot on the island of Crete is part of the Global Observation Research Initiative in Alpine Environments (GLORIA) monitoring network. The paper examines species and vegetation changes with respect to climate and altitude over a seven-year period (2001–2008) at a range of spatial scales (10 m Summit Area Section-SAS, 5 m SAS, 1 m2) using the GLORIA protocol in a re-survey of four mountain summits (1664 m–2339 m). The absolute species loss between 2001–2008 was 4, among which were 2 endemics. At the scale of individual summits, the highest changes were recorded at the lower summits with absolute species loss 4 in both cases. Paired t-tests for the total species richness at 1 m2 between 2001–2008, showed no significant differences. No significant differences were found at the individual summit level neither at the 5 m SAS or the 10 m SAS. Time series analysis reveals that soil mean annual temperature is increasing at all summits. Linear regressions with the climatic variables show a positive effect on species richness at the 5 m and 10 m SAS as well as species changes at the 5 m SAS. In particular, June mean temperature has the highest predictive power for species changes at the 5 m SAS. Recorded changes in species richness point more towards fluctuations within a plant community’s normal range, although there seem to be more significant diversity changes in higher summits related to aspects. Our work provides additional evidence to assess the effects of climate change on plant diversity in Mediterranean mountains and particularly those of islands which remain understudied.

scholarly journals Regional typology of spring vegetation in Parc Ela (Grisons, Switzerland)

2021 ◽  
Vol 2 ◽  
pp. 257-274
Author(s):  
Hallie Seiler ◽  
Daniel Küry ◽  
Regula Billeter ◽  
Jürgen Dengler
Keyword(s):  
Species Richness ◽  
Environmental Variables ◽  
Vascular Plant ◽  
Detrended Correspondence Analysis ◽  
Conservation Strategy ◽  
Soil Reaction ◽  
Ecological Indicator ◽  
Ecological Value ◽  
Water Conductivity ◽  
Regional Survey

Aims: The spring habitats of Central Europe are insular biotopes of high ecological value. Although subject to severe exploitation pressures, they do not yet have a comprehensive protection status in Switzerland. Contributing to this challenge is the controversy involved with their syntaxonomic classification. In the context of the development of a regional conservation strategy and the establishment of a national inventory of Swiss springs, we carried out a regional survey of spring vegetation and aimed to translate this into a classification system. Study area: Montane and subalpine zones of Parc Ela (Grisons, Switzerland). Methods: We selected 20 springs to cover different regions, elevations and bedrock types within the park. In each of them we recorded complete vascular plant and bryophyte composition as well as a range of environmental variables in three 1-m² plots that were placed to reflect the heterogeneity within the spring. After running an unsupervised classification with modified TWINSPAN, the distinguished vegetation units were characterized in terms of diagnostic species, species richness and environmental variables and placed within the syntaxonomic system. Results: Species richness was high (total species 264, mean 21.7 species in 1 m2). The two most important environmental gradients of the ordination were elevation/water conductivity and insolation/water pH/soil reaction EIV. We distinguished seven communities within two main groups. Conclusions: All unshaded springs, including those over siliceous bedrock, could be assigned to a broadly defined Cratoneurion. The petrifying springs were not strongly distinguishable floristically from other base-rich springs. The forest springs, although often not clearly differentiated from their unshaded counterparts, could be provisionally divided into the alliances Caricion remotae and Lycopodo europaei-Cratoneurion commutati. As there is a certain threat to these habitats in the park due to anthropogenic influence, protection measures are recommended, most importantly the appropriate management of alpine pastures. Taxonomic reference: Juillerat et al. (2017) for vascular plants, Meier et al. (2013) for bryophytes. Abbreviations: ANOVA = analysis of variance; DCA = detrended correspondence analysis; EIV = ecological indicator value; FOEN = Federal Office of the Environment (Switzerland); NCHO = Ordinance on the Protection of Nature and Cultural Heritage; SD = standard deviation; TWINSPAN = Two Way Indicator Species Analysis; WPA = Federal Act on the Protection of Waters.

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

Ecological impacts of wheat seeding after a Sierra Nevada wildfire

2004 ◽  
Vol 13 (1) ◽  
pp. 73 ◽  
Author(s):  
Jon E. Keeley
Keyword(s):  
Species Richness ◽  
Sierra Nevada ◽  
Ponderosa Pine ◽  
Seedling Recruitment ◽  
Vascular Plant ◽  
Ecological Impact ◽  
Ground Surface ◽  
Ecological Impacts ◽  
Total Species Richness ◽  
Giant Sequoia

The Highway Fire burned 1680 ha of mixed ponderosa pine–oak–chaparral in the newly created Giant Sequoia National Monument and the adjacent Sequoia National Forest of Fresno County, California in August 2001. The USDA Forest Service Burned Area Emergency Rehabilitation (BAER) program recommended that portions of the burned forest be seeded with a non-persistent variety of wheat at a density of 157 kg ha–1 (140 lb/ac). The present study compared the vascular plant diversity and cover in seeded and unseeded parts of this burn to evaluate the ecological impact of seeding an alien grass. In the first post-fire growing season, the natural regeneration of unseeded control sites averaged ~55% ground surface covered. Wheat seeding enhanced the ground cover, averaging 95% ground surface cover. Wheat was the dominant species on the seeded sites, comprising 67% of the total cover. Dominance–diversity curves were markedly affected by the seeding and indicated a disruption in the natural ecological structure of these communities. On seeded sites, wheat dominated and all other species were poorly represented whereas, on unseeded control sites, there was a more equitable distribution of species. Correlated with the wheat cover was a significant decrease in species richness at all scales examined. Total species richness was reduced from 152 species across all unseeded sites to 104 species on all seeded sites. Average species richness, at scales from 1 to 1000 m2, was 30–40% lower on seeded sites. Species most strongly inhibited were post-fire endemics whose lifecycle is restricted to immediate post-fire environments. Seeded sites had fewer alien species than unseeded sites; however, this may not have any lasting effect since other studies show the primary alien threat is not in the first post-fire year. Seeding was also associated with an order of magnitude drop in Pinus ponderosa seedling recruitment and, coupled with the massive thatch still remaining on the site, it is likely that recruitment will be inhibited in subsequent years.

scholarly journals Patterns in vascular plant species density in tall alpine herbfield along an increasing altitudinal gradient in an Australian alpine region

2009 ◽  
Vol 57 (3) ◽  
pp. 210 ◽  
Author(s):  
Catherine M. Pickering ◽  
Sarah Butler
Keyword(s):  
Species Richness ◽  
Plant Community ◽  
Vascular Plant ◽  
Alpine Region ◽  
Species Density ◽  
Location Data ◽  
Total Species Richness ◽  
Community Boundaries ◽  
Total Composition ◽  
Total Species

Patterns in species density and richness per altitudinal interval have been found when sampling across plant-community boundaries, including in the largest contiguous alpine area in Australia. To see if similar patterns occur within a single community, vascular-plant composition was systematically sampled with replicate nested quadrats of increasing size (0.01, 0.06, 0.25, 1.00, 4.00, 25.00, 49.00 and 100-m2 size) sampled from ~1850-m to 2100-m altitude in tall alpine herbfield, Australia. The only significant relationships with altitude were quadratic relationships for the density of herb and graminoid species, with peak density at middle altitudes and a linear decline in total species richness with altitude for 0.06-m2 quadrats. The composition of 100-m2 quadrats was unrelated to altitude when tested with analysis of similarity for total composition, whereas the relationship was significant for growth-forms and the origin (local endemics, Australia endemics and weeds) of species. Location data from this, and 11 other studies were used to compare the species richness of more of the flora (183 species) in 50-m altitudinal bands. There were significant quadratic relationships for total species richness and the number of herb and shrub species, with a peak in richness at ~2000 m. Therefore, altitude does affect species richness overall in this alpine region, although it has only a weak effect on species density within the most common plant community.

scholarly journals Effects of reindeer density on vascular plant diversity on North Scandinavian mountains

Rangifer ◽  
2005 ◽  
Vol 25 (1) ◽  
pp. 5 ◽  
Author(s):  
Johan Olofsson ◽  
Lauri Oksanen
Keyword(s):  
Species Richness ◽  
Vascular Plants ◽  
Vascular Plant ◽  
Detrended Correspondence Analysis ◽  
Diversity Indices ◽  
Rare Plants ◽  
Strong Impact ◽  
Total Species Richness ◽  
Species Lists ◽  
Mountain Chain

We studied the effects of reindeer grazing on species richness and diversity of vascular plants on dolomite influenced low alpine sites in the species rich northern part of the Scandes using 8 sites with different reindeer densities. Two sites were situated inside Malla Strict Nature Reserve, where reindeer grazing have been totally prohibited since 1981, and strongly restricted since 1950s. The six other sites were located in other species rich hotspot sites standardized to be as similar to the dolomite-influenced sites in Malla Strict Reserve as possible but varying in reindeer densities commonly found in the Fennoscandian mountain chain. Each site with a habitat complex especially rich in rare vascular plants (the Dryas heath – low herb meadow complex) was systematically sampled in four plots of 2 m x 10 m. The plots were divided to 20 squares of 1 m x 1 m, and complete species lists of vascular plants were compiled for each of the squares. The first DCA (detrended correspondence analysis) axis was strongly related to an index of reindeer grazing, indicating that grazing has a strong impact on the composition of the vegetation. None of the characteristics indices of biodiversity (species richness, evenness or Shannon-Wiener H’) was correlated with reindeer density. The local abundances of categories consisting of relatively rare plants (Ca favored plants and red listed plants of Finland) showed significant, positive correlation with the intensity of reindeer grazing. We conclude that even though the density of reindeer has no influence on the total species richness or diversity of vascular plants, reindeer may still be important for regional biodiversity as it seems to favour rare and threatened plants. Moreover, our results imply that standard diversity indices may have limited value in the context of conservation biology, as these indices are equally influenced by rarities and by trivial species.Abstract in Swedish / Sammandrag: Vi studerade hur renbete påverkar kärlväxtflorans artrikedom och diversitet på dolomitpåverkade lågalpina lokaler i de artrikaste delarna av norra Fennoskandien. Vi inventerade 8 lokaler med olika rentätheter. Två lokaler ligger inom Malla Nationalpark, där renar har varit förbjudna sedan 1981 och starkt begränsade sedan 1950-talet. De sex andra lokalerna ligger i andra artrika områden med samma dolomitdominerade berggrund, men är betade av renar. Rentätheterna vid de studerade lokalerna varierar från helt obefintligt till bland de högsta rentätheter man kan finna i Fennoskandien. Inventeringen utfördes genom att systematiskt undersöka fyra 2 m x 10 m stora ytor i varje lokal i en habitattyp som är speciellt rik i ovanliga kärlväxter (fjällsippehed-lågörtsäng komplex). Varje yta delades upp i 20 småytor (1 m x 1 m), och en total artlista upprättades för var och en av dessa småytor. Den första axeln i DCA (detrended correspondence analyses) analysen korrelerade med rentätheten. Det visar att renar påverkar sammansättningen av växtsamhället. Ingen av de vanliga måtten på biodiversitet (artrikedom eller Shannon-Wiener diversitetsindex) var korrelerade med rentätheten. Trots detta, var tätheterna av Ca-gynnade växter och arter rödlistade i Finland positivt korrelerade med rentätheten. Trots att renarna inte påverkade totala artrikedommen, kan de vara betydelsefulla för regionala biodiversiteten eftersom de gynnar ovanliga och hotade arter. De vanliga måtten på biodiversitet har begränsat värde för bevarandebiologiska frågeställningar, eftersom de är lika känsliga för ovanliga och vanliga arter.

scholarly journals Interpolated Altitudinal Species Richness in Arghakhachi District of Nepal

2020 ◽  
Vol 25 (1) ◽  
pp. 52-60
Author(s):  
Babu Ram Nepali ◽  
John Skartveit ◽  
Chitra Bahadur Baniya
Keyword(s):  
Species Richness ◽  
Plant Species ◽  
Vascular Plant ◽  
Plant Species Richness ◽  
Climatic Variables ◽  
Annual Rainfall ◽  
Altitudinal Distribution ◽  
Vascular Plant Species ◽  
Total Species Richness ◽  
Richness Pattern

 The magnitude of climatic variables over space and time determines the altitudinal variation of species richness. The present study has been carried out to determine the vascular plant species richness patterns along with altitude in the Arghakhanchi district (27° 45' to 28º 06' N and 80° 45' to 83° 23' E), West Nepal. The published literature related to the altitudinal distribution of vascular plant species in Arghakhanchi district was collected and enlisted a total of 597 species. The altitudinal range of the Arghakhanchi district was 200-2300 meters above sea level (masl) which was divided equally into 21 bands of 100 m each. The total number of vascular species that occurred at each 100 m contour elevation was considered as the species richness. The objective of this study was to find the vascular plant species richness pattern in Arghakhanchi district concerning altitude and climatic variables. The generalized linear model (GLM) was applied to the total species richness against altitude, annual mean temperature (AMT), and mean annual rainfall (MAR). Total vascular species richness showed a statistically significant unimodal pattern with a maximum richness of 471 species at 1300 masl (r2= 0.91; p < 0.001). Likewise, gymnosperm, dicot, monocot, and pteridophyte species richness showed a highly significant unimodal altitudinal richness pattern. Altitudes of modeled maximum species richness were found varied according to the taxa.

scholarly journals The influence of dynamic environmental interactions on detection efficiency of acoustic transmitters in a large, deep, freshwater lake

2019 ◽  
Vol 7 (1) ◽  
Author(s):  
Natalie V. Klinard ◽  
Edmund A. Halfyard ◽  
Jordan K. Matley ◽  
Aaron T. Fisk ◽  
Timothy B. Johnson
Keyword(s):  
Study Design ◽  
Environmental Conditions ◽  
Power Output ◽  
Environmental Variables ◽  
Acoustic Telemetry ◽  
Detection Efficiency ◽  
Data Interpretation ◽  
Heterogeneous Environments ◽  
Depth Range ◽  
Dynamic Relationship

Abstract Background Acoustic telemetry is an increasingly common method used to address ecological questions about the movement, behaviour, and survival of freshwater and marine organisms. The variable performance of acoustic telemetry equipment and ability of receivers to detect signals from transmitters have been well studied in marine and coral reef environments to inform study design and improve data interpretation. Despite the growing use of acoustic telemetry in large, deep, freshwater systems, detection efficiency and range, particularly in relation to environmental variation, are poorly understood. We used an array of 90 69-kHz acoustic receivers and 8 sentinel range transmitters of varying power output deployed at different depths and locations approximately 100–9500 m apart for 215 days to evaluate how the detection efficiency of acoustic receivers varied spatially and temporally in relation to environmental conditions. Results The maximum distance that tags were detected ranged from 5.9 to 9.3 km. Shallow tags consistently had lower detection efficiency than deep tags of the same power output and detection efficiency declined through the winter months (December–February) of the study. In addition to the distance between tag and receiver, thermocline strength, surface water velocity, ice thickness, water temperature, depth range between tag and receiver, and number of fish detections contributed to explaining variation in detection efficiency throughout the study period. Furthermore, the most significant models incorporated interactions between several environmental variables and tag–receiver distance, demonstrating the complex temporal and spatial relationships that exist in heterogeneous environments. Conclusions Relying on individual environmental variables in isolation to interpret receiver performance, and thus animal behaviour, may be erroneous when detection efficiency varies across distances, depths, or tag types. As acoustic telemetry becomes more widely used to study ecology and inform management, it is crucial to understand its limitations in heterogeneous environments, such as freshwater lakes, to improve the quality and interpretation of data. We recommend that in situ range testing and retrospective analysis of detection efficiency be incorporated into study design for telemetry projects. Furthermore, we caution against oversimplifying the dynamic relationship between detection efficiency and environmental conditions for the sake of producing a correction that can be applied directly to detection data of tagged animals when the intended correction may not be justified.

scholarly journals Effect of tree species identity and related habitat parameters on understorey bryophytes – interrelationships between bryophyte, soil and tree factors in a 50-year-old experimental forest

2021 ◽  
Author(s):  
Kaja Rola ◽  
Vítězslav Plášek ◽  
Katarzyna Rożek ◽  
Szymon Zubek
Keyword(s):  
Species Richness ◽  
Tree Species ◽  
Forest Floor ◽  
Vascular Plant ◽  
Soil Parameters ◽  
Species Identity ◽  
Habitat Factors ◽  
Positive Correlations ◽  
Old Trees ◽  
Habitat Parameters

Abstract Aim Overstorey tree species influence both soil properties and microclimate conditions in the forest floor, which in turn can induce changes in ground bryophyte communities. The aim of the study was to investigate the effect of tree species identity and the most important habitat factors influencing understorey bryophytes. Methods We assessed the effect of 14 tree species and related habitat parameters, including soil parameters, vascular plant presence and light intensity on bryophytes in monospecific plots covered by nearly fifty-year-old trees in the Siemianice Experimental Forest (Poland). Results The canopy tree species determined bryophyte species richness and cover. The strongest differences were observed between plots with deciduous and coniferous trees. Soils with a more acidic pH and lower content of macronutrients supported larger bryophyte coverage. We also found a positive correlations between vascular plants and availability of light as well as bryophyte species richness. Conclusion Tree species identity and differences in habitat conditions in the forest floor lead to changes of ground bryophyte richness, cover and species composition. Consequently, the changes in the dominant tree species in the stand may result in significant repercussions on ground bryophyte communities. We indicated that the introduction of alien tree species, i.e. Quercus rubra, has an adverse effect on bryophyte communities and suggested that the selection of tree species that contribute to the community consistent with the potential natural vegetation is highly beneficial for maintaining ground bryophyte biodiversity.

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