Abundance Of Vascular Plant Species Research Articles

Structural shifts in plant functional diversity during biogeomorphic succession: Moving beyond taxonomic investigations in an alpine glacier foreland

AbstractThe complex interrelation between plants and geomorphic processes is described in the concept of biogeomorphic succession. While ecological research on succession and community assembly has transitioned towards functional approaches, studies on functional diversity in biogeomorphic settings, particularly in glacier forelands, remain limited. In this study, we investigated abundance of vascular plant species and functional traits in an alpine glacier foreland using data from 199 plots. Our objective was to unravel the development of functional diversity during biogeomorphic succession. Specifically, the study determined whether structural shifts in functional diversity are associated with stability thresholds related to plant cover, geomorphic influence, and examined trait spectra for stages of biogeomorphic succession. Our findings revealed a nonlinear trajectory of functional diversity along the plant cover gradient, marked by two distinct structural shifts at 30% and 74% cover, corresponding to established stability thresholds. Along the gradient of geomorphic influence, we observed an increase in functional diversity until 54% of the plot area was affected, beyond which functional diversity declined below the initial level. The analysis of community‐weighted means of traits across four stages of biogeomorphic succession determined by plant cover and absence and presence of geomorphic influence revealed significant differences in trait values. In the transition to the biogeomorphic stage, associated with the identified initial structural shift, there is a shift from a prevalence of above‐ground adaptation and reproductive traits, such as leaf longevity, structure, growth form and mixed reproductive strategies, to an increased dominance of competitor species and traits related to below‐ground structures, including root type and structures, as well as vegetative reproduction. Our results contribute to understanding the relationship between vegetation succession and geomorphic influence by linking them to plant functional traits. This study advances beyond traditional taxonomic investigations by emphasizing functional approaches to biogeomorphic succession. Moreover, the functional trait data used in this study, easily downloadable from a public repository, can serve as a valuable template for future research in (bio)geomorphology, along with the employed methodologies.

Impact of Short-Term Abandonment on the Structure and Functions of Semi-Natural Dry Grasslands

AbstractA study of the impact of short-term abandonment on the structure and functions of semi-natural dry grasslands in Lithuania was performed. Data on the abundance of vascular plant species, hay and litter samples were collected. At the same time, plant functional traits and Ellenberg indicator values were used to evaluate the effect of abandonment on the structure and functions of semi-natural dry grasslands. The results showed that litter layer was significantly heavier in unmanaged plots compared to that in managed plots. The vascular plant species pool was higher in managed plots, where 62 vascular plant species were identified, while in unmanaged plots 46 species were identified. The species richness was significantly higher in managed semi-natural dry grasslands. Unmanaged plots had 12.3 ± 0.6 species, while managed plots had 17.7 ± 1.2 species per one square metre. Functional plant traits were similar in mowed and abandoned communities, while functional diversity was lower in unmanaged communities. These results are a clear indicator that the managing of semi-natural dry grasslands creates heterogeneity of the environment.

Spatio-temporal distribution of vascular plant species abundance on Qinghai-Tibet Plateau

For quantitatively explaining the correlations between the vascular plant species abundance (VPSA) and habitat factors, a spatial simulation method has been developed to simulate the distribution of VPSA on the Qinghai-Tibet Plateau. In this paper, the vascular plant type, land cover, mean annual biotemperature, average total annual precipitation, topographic relief, patch connectivity and ecological diversity index were selected to screen the best correlation equation between the VPSA and habitat factors on the basis of 37 national nature reserves on the Qinghai-Tibet Plateau. The research results show that the coefficient of determination between VPSA and habitat factors is 0.94, and the mean error is 2.21 types per km2. The distribution of VPSA gradually decreases from southeast to northwest, and reduces with increasing altitude except the desert area of Qaidam Basin. Furthermore, the scenarios of VPSA on the Qinghai-Tibet Plateau during the periods from 1981 to 2010 (T0), from 2011 to 2040 (T2), from 2041 to 2070 (T3) and from 2071 to 2100 (T4) were simulated by combining the land cover change and the climatic scenarios of CMIP5 RCP2.6, RCP4.5 and RCP8.5. The simulated results show that the VPSA would generally decrease on the Qinghai-Tibet Plateau from T0 to T4. The VPSA has the largest change ratio under RCP8.5 scenario, and the smallest change ratio under RCP2.6 scenario. In general, the dynamic change of habitat factors would directly affect the spatial distribution of VPSA on the Qinghai- Tibet Plateau in the future.

Effect of clear-cutting on the understory vegetation, soil and diversity of litter beetles in scots pine-dominated forest

ABSTRACTCurrently, the aim of modern forest management is not only timber production but also the protection of biodiversity. The initial effects of clear-cut logging on forest understory vegetation, soil and the diversity of litter beetles have been studied. We examined unstudied effects of clear-cutting disturbance on understory vascular plant species abundance, forest soils, and understory vegetation nutrients as well as beetle diversity one year after clear-cutting. Substantial changes in the prominence values and above-ground mass of forest-related vascular plant and moss species were detected. Clear-cuttings resulted in fast appearance of new light-loving plant species. The significant decrease in understory plant biomass influenced the reduction of nutrient pools in clear-cut areas after one year. The clear-cut logging negatively influenced the richness of species and the number of individuals of stenobiontic forest-related beetles in the forest litter. However, forest clear-cuttings were beneficial for eurytopic and open land species.

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

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

Does functional soil microbial diversity contribute to explain within-site plant β-diversity in an alpine grassland and adehesameadow in Spain?

SummaryQuestions Once that the effects of hydrological and chemical soil properties have been accounted for, does soil microbial diversity contribute to explain change in plant community structure (i.e. within-site beta-diversity)? If so, at which spatial scale does microbial diversity operate? Location: La Mina in Moscosa Farm, Salamanca, western Spain (dehesa community) and Laguna Larga in the Urbion Peaks, Soria, central-northern Spain (alpine grassland). Methods The abundance of vascular plant species, soil gram-negative microbial functional types and soil chemical properties (pH, available phosphorus, and extractable cations) were sampled at both sites, for which hydrological models were available. Redundancy analysis (RDA) was used to partition variation in plant community structure into hydrological, chemical and microbial components. Spatial filters, arranged in scalograms, were used to test for the spatial scales at which plant community structure change. Results In the case of the dehesa the diversity of soil gram-negative microbes, weakly driven by soil pH, contributed to a small extent (adj-R2 = 2%) and at a relative medium spatial scale to explain change in plant community structure. The abundance of a few dehesa species, both annual (Trifolium dubium, Vulpia bromoides) and perennial (Poa bulbosa, Festuca ampla), was associated with either increasing or decreasing soil microbial diversity. In the alpine meadow the contribution was negligible. Conclusions Microbial diversity can drive community structure, though in the hierarchy of environmental factors structuring communities it appears to rank lower than other soil factors. Still, microbial diversity appears to promote or restrain individual plant species. This paper aims to encourage future studies to use more comprehensive and insightful techniques to assess microbial diversity and to combine this with statistical approaches such as the one used here. This article is protected by copyright. All rights reserved.

What is the most efficient and effective method for long-term monitoring of alpine tundra vegetation?

Nondestructive estimations of plant community characteristics are essential to vegetation monitoring programs. However, there is no universally accepted method for this purpose in the Arctic, partly because not all programs share the same logistical constraints and monitoring goals. Our aim was to determine the most efficient and effective method for long-term monitoring of alpine tundra vegetation. To achieve this, we established 12 vegetation-monitoring plots on a south-facing slope in the alpine tundra of southern Yukon Territory, Canada. Four observers assessed these plots for vascular plant species abundance employing three methods: visual cover (VC) and subplot frequency (SF) estimation and modified point-intercept (PI) (includes rare species present but not intersected by a pin). SF performed best in terms of time required per plot and sensitivity to variations in species richness. All methods were similarly poor at estimating relative abundance for rare species, but PI and VC were substantially better at high abundances. Differences among methods were larger than among observers. Our results suggest that SF is best when the monitoring focus is on rare species or species richness across extensive areas. However, when the focus is on monitoring changes in relative abundance of common species, VC or PI should be preferred.

Arbuscular mycorrhizal fungi and vascular plant species abundance and community structure in tallgrass prairies with varying agricultural disturbance histories

Tallgrass prairie is one of the most critically endangered habitats in Canada, with less than one percent of its original extent remaining. Information on arbuscular mycorrhizal fungi (AMF) in Canadian prairie, which may be beneficial to tallgrass prairie restoration, is lacking. We conducted a descriptive ecological study of the communities of arbuscular mycorrhizal fungi (AMF) and vascular plants at five former or extant tallgrass prairie sites on Walpole Island First Nation, Ontario: one undisturbed prairie, two naturally recovered prairies and two old fields abandoned from agriculture 19 and 3 years ago, respectively. The AMF were identified morphologically using spores from trap cultured soil samples, and the number of spores of each taxon was used as an estimate of their abundance. We performed ester linked extraction and measured fungal lipid biomarkers to assay the biomass of AMF. Sixteen species of AMF and 111 plant species were identified. Species composition, richness and diversity of both AMF and plants varied among sites. Principal component analysis distinguished fungal and plant communities at tallgrass prairie sites from those at more recently disturbed fields. However, AMF biomass, as assessed by the concentration of the fatty acid methyl esters C16:1cis11 and C18:1cis11, was not significantly different between old fields and tallgrass prairie. Community composition of AMF was a better indicator of agricultural disturbance than AMF abundance, species richness, or biomass. Therefore, if AMF play an important role in the reestablishment of tallgrass prairie plant species, it is most likely through plant host specificity with particular species or taxonomic groups in the AMF community.

Determinants of plant community composition of remnant biancane badlands: a hierarchical approach to quantify species-environment relationships

Question: Which environmental variables best explain patterns in the vegetation of biancane badlands? What is the role of spatial scales in structuring the vegetation of biancane badlands within the agricultural matrix? Location: Five biancane badlands in Central Italy (Tuscany). Methods: An object-oriented approach on high-resolution multispectral images was used to classify physiognomic vegetation types in five biancane badlands. Within each badland, data on vascular plant species abundance were collected using a stratified random design. Variation partitioning based on partial redundancy analysis was used to evaluate the contribution of three sets of environmental predictors, recorded at the spatial scales of plot, patch and biancane badland in explaining patterns in plant community composition. Results: Environmental variables included in the final model ‐ electrical conductivity and carbon/nitrogen ratio (plot scale), shape index (patch scale) and area (biancane badland scale) ‐ accounted for 15.5% of the total variation in plant community composition. Soil characteristics measured at the plot level explained the majority of variation. In the smallest badlands, Bromus erectus perennial grasslands were absent, while annual grasslands, linked with harsh soil conditions (i.e. high soil salinity), were not affected by either the surface area of biancane badlands or by the soil nitrogen availability. Conclusions: The identification of the major predictors of patterns in remnant vegetation requires conducting investigations at multiple spatial scale. Management strategies should operate at different spatial scale, preventing any further reduction in the size of existing badlands and relying on habitat- instead of area-focused conservation practices.

Linking environmental gradients, species composition, and vegetation indicators of sugar maple health in the northeastern United States

Sugar maple ( Acer saccharum Marsh.) decline has occurred throughout its range over the past 50 years, although decline symptoms are minimal where nutritional thresholds of Ca, Mg, and Mn are met. Here, we show that availability of these elements also controls vascular plant species composition in northern hardwood stands and we identify indicator species of these nutrient thresholds. Presence and abundance of vascular plant species and data on 35 environmental variables were collected from 86 stands in New Hampshire and Vermont (NHVT) and Pennsylvania and New York (PANY). Nonmetric multidimensional scaling ordination was used to determine which variables affected presence and abundance of species; both measures gave similar results. A base cation – acid cation nutrient gradient on axis one accounted for 71.9% (NHVT) and 63.0% (PANY) of the variation in the nonmetric multidimensional scaling ordination. Measures of Ca, Mg, and pH formed the base end and Al, Mn, K, soil acidity, and organic matter the acid end in both subregions. In both subregions, sugar maple foliar Mg and Ca had the strongest association with the base end of axis 1; exchangeable Al in NHVT and foliar Mn in PANY were strongly associated with the acid end. McNemar’s exact test and indicator species analysis were used to determine which species were present in stands that met the nutritional thresholds for Ca, Mg, and Mn foliar chemistry. McNemar’s exact test identified 16 species in NHVT and PANY, 16 additional species in NHVT only, and 12 additional species in PANY only. Indicator species analysis identified a subset of these species with the highest frequency of occurrence. Indicator species could provide land managers with a diagnostic tool for determining where on the landscape sugar maple is “at risk” or likely to remain healthy in the face of stresses.

Is the relative abundance of nonnative species an integrated measure of anthropogenic disturbance?

The hypothesis that the percentage of nonnative plant species inhabiting a landscape might be used as an integrated measure of anthropogenic disturbance was explored in 26 diverse landscape parcels in Rhode Island. Nine correlates of anthropogenic disturbance within, and immediately adjacent to the refuges were compared to two refuge-specific indices of relative nonnative vascular plant species abundance. The percentage of the total vascular flora of each refuge that was nonnative was the Nonnative Index for each refuge. The percentage of all nonnative species in the 26 refuges combined that occurred in a given refuge was the Regional Nonnative Index for each refuge (nonnative species in each refuge divided by the nonnative species in all 26 refuges, times 100). The latter index measured how successful species from the finite pool of nonnative species present in the region were at invading and colonizing a refuge. Of the 869 vascular plant species in all 26 refuges, 28% were nonnative. The percentage of the vascular flora that was nonnative in each refuge varied from 2 to 50%. Few comparisons between correlates of anthropogenic disturbance and Nonnative Indices were statistically significant, yet two of the nine correlates of anthropogenic disturbance were highly related to Regional Nonnative Indices. Collectively, the correlates of anthropogenic disturbance accounted for 39% of the variance in the Regional Nonnative Index for all species combined, and 56% of the variance in the Regional Nonnative Index for tree species alone. The Regional Nonnative Index was also highly related to the richness of native plant species. The hypothesis that the nonnative vascular plant diversity of a landscape can be used as a surrogate for the integrated effects of anthropogenic disturbance was generally rejected by the analysis of our Nonnative Index, and supported by the analysis of our Regional Nonnative Index.

The early impact of adjacent clearcutting and forest fire on riparian zone vegetation in northwestern Ontario

The distribution and abundance of vascular plant species in riparian communities was compared between three levels of disturbance in the adjacent upland vegetation. Comparisons were made between riparian zone sites that were undisturbed, sites where clearcuts were separated from the riparian zone by a buffer of upland forest, and sites where a forest fire had burned to the riparian zone-upland ecotone. No significant differences in the overall abundance and distribution of species in the riparian vegetation were found between the three disturbance classes, though a small number of species appeared to increase in abundance at burn sites. These results demonstrate that disturbances in the upland forest do not seriously impact the riparian zone plant community, likely because the riparian species are adapted to a high-light environment and flooding disturbance. The environmental factors that change in the riparian zone following removal of the adjacent forest canopy, including light levels, temperature, and wind penetration, do not appear to have a significant influence on the riparian zone vegetation. These results suggest that aspects of the current riparian management guidelines in northwestern Ontario may need to be re-evaluated.