scholarly journals Ground vegetation diversity and geobotanical analysis in dune pine forests in southwest Estonia

2018 ◽  
Vol 69 (1) ◽  
pp. 63-74 ◽  
Author(s):  
Mari Tilk ◽  
Katri Ots ◽  
Tea Tullus ◽  
Malle Mandre
Keyword(s):  
Electrical Conductivity ◽  
Species Richness ◽  
Species Composition ◽  
Water Content ◽  
Soil Ph ◽  
Vascular Plant ◽  
Lichen Species ◽  
Ground Vegetation ◽  
Light Conditions ◽  
Vegetation Species

Abstract To investigate the ecosystems on dunes, five typical dunes were selected in the coastal area of the Baltic Sea in southwest Estonia. To study ground vegetation species richness, species composition and horizontal structure, 251 quadrats of 1 m2 in size were established and descriptions of vascular plants, bryophytes and lichen species were provided. Topographical factors, soil horizons, soil pH and electrical conductivity, soil nutrients, soil moisture conditions and light conditions were determined. In total, 42 vascular plant, 43 bryophyte and 48 lichen species were recorded on five dunes. Vascular plant species richness and composition on forested dunes was dependent on the absolute dune height, zone and aspect of the slope, soil nitrogen, potassium and phosphorus content, soil pH and moisture, the cover of the bryophyte-lichen layer and light conditions. Regarding bryophyte and lichen layer species composition, important factors were the aspect of the dune, vascular plant species cover, light conditions, the thickness of the moderately decomposed organic soil horizon, soil pH, electrical conductivity and volumetric water content. Lichen species richness was highest on the slopes of the dunes, while bryophyte species richness was higher at the bottoms and decreased towards the tops of the dunes. Ground vegetation species richness and species’ horizontal and vertical structure on forested dunes were highly dependent on topography-induced differences, aspect, height and zone of the dunes. The most important factors controlling the complex of ground vegetation were light conditions, soil water content, thickness of the moderately decomposed litter layer and soil potassium and calcium content.

scholarly journals Effect of environmental factors on the composition of terrestrial bryophyte and lichen species in Scots pine forests on fixed sand dunes

2018 ◽  
Vol 27 (3) ◽  
pp. e015 ◽  
Author(s):  
Mari Tilk ◽  
Katri Ots ◽  
Tea Tullus
Keyword(s):  
Electrical Conductivity ◽  
Species Richness ◽  
Environmental Factors ◽  
Water Content ◽  
Soil Ph ◽  
Sand Dunes ◽  
Vascular Plant ◽  
Volumetric Water Content ◽  
Lichen Species ◽  
Organic Horizon

Aim of the study: To investigate terrestrial bryophyte and lichen species richness and environmental factors affecting the composition of species.Area of the study: Four Boreal zone fixed dunes were selected in the coastal area of the Baltic Sea in southwest Estonia.Material and methods: Non-metric multidimensional scaling was performed to analyse distribution patterns and environmental factors like canopy cover, photosynthetically active radiation, soil organic horizon thickness and decomposition rates, soil volumetric water content, soil pH and electrical conductivity and soil nutrients correlated with bryophyte and lichen species composition.Main results: Thirty bryophytes and 22 lichens were found on 232 sample plots, the most frequent species were Pleurozium schreberi (Willd. ex Brid.) Mitt., Hylocomium splendens (Hedw.) Schimp., Dicranum polysetum Sw. ex anon., Cladonia arbuscula (Wallr.) Flot. and Cladonia furcata (Huds.) Schrad. The lichen species richness was highest on the slopes of the dunes and decreased towards the bottoms and tops; bryophyte species richness was higher on the bottoms and decreased towards the tops of the dunes.Research highlights: The composition of bryophytes and lichens is significantly influenced by the aspect and the location on the dune, light conditions, soil pH, soil salinity (measured as electrical conductivity) and volumetric water content, thickness of moderately decomposed organic horizon and vascular plant species cover.KeywordsInland dunes; terrestrial bryophyte and lichen communities; environmental factors; topography.

scholarly journals Influence of Soil Water Content on the Vegetation Species Richness in Qinghai Lake Inland Alpine Wetland

2011 ◽  
Vol 10 ◽  
pp. 2426-2430 ◽  
Author(s):  
Zhu Jinfu ◽  
Chen Kelong ◽  
Wu Yanpeng ◽  
Cao Guangchao ◽  
Cao Shengkui ◽  
...  
Keyword(s):  
Species Richness ◽  
Water Content ◽  
Soil Water ◽  
Soil Water Content ◽  
Qinghai Lake ◽  
Alpine Wetland ◽  
Vegetation Species

scholarly journals On the calculation of the topographic wetness index: evaluation of different methods based on field observations

2005 ◽  
Vol 2 (4) ◽  
pp. 1807-1834 ◽  
Author(s):  
R. Sørensen ◽  
U. Zinko ◽  
J. Seibert
Keyword(s):  
Species Richness ◽  
Soil Moisture ◽  
Soil Ph ◽  
Groundwater Level ◽  
Vascular Plant ◽  
Plant Species Richness ◽  
Topographic Wetness Index ◽  
Wetness Index ◽  
Forest Sites ◽  
The Way

Abstract. The topographic wetness index (TWI, ln(a/tanβ)), which combines local upslope contributing area and slope, is commonly used to quantify topographic control on hydrological processes. Methods of computing this index differ primarily in the way the upslope contributing area is calculated. In this study we compared a number of calculation methods for TWI and evaluated them in terms of their correlation with the following measured variables: vascular plant species richness, soil pH, groundwater level, soil moisture, and a constructed wetness degree. The TWI was calculated by varying six parameters affecting the distribution of accumulated area among downslope cells and by varying the way the slope was calculated. All possible combinations of these parameters were calculated for two separate boreal forest sites in northern Sweden. We did not find a calculation method that performed best for all measured variables, but we were able to identify the general characteristics of the best methods for different groups of measured variables. The results provide guidelines for choosing the best method for estimating species richness, soil pH, groundwater level, and soil moisture by the TWI derived from digital elevation models.

scholarly journals Effect of environmental and spatial factors on small-sized fish assemblages in a tropical river

2021 ◽  
Vol 51 (2) ◽  
pp. 129-138
Author(s):  
Izaias Médice FERNANDES ◽  
Katiele de Jesus SACOMAN ◽  
José Paulo de FARIAS-NETO ◽  
Hugmar Pains da SILVA ◽  
Jhony VENDRUSCOLO ◽  
...  
Keyword(s):  
Electrical Conductivity ◽  
Species Richness ◽  
Species Composition ◽  
Environmental Variables ◽  
Fish Assemblages ◽  
Negative Relationship ◽  
Dispersal Limitation ◽  
River Continuum ◽  
Spatial Factors ◽  
Water Characteristics

ABSTRACT The river continuum concept predicts that gradual changes in river geomorphology and hydrology can drive longitudinal changes in aquatic community structure. Accordingly, we evaluated how environmental variables (electrical conductivity, pH, water transparency and water velocity), spatial factors (distance from headwaters and Moran’s eigen vector maps - MEMs), and the presence of dams affect small-sized fish assemblages along a 105-km stretch of the upper Branco River, a tributary in the Madeira River, Amazonas Basin, Brazil. Seine-net based collections were carried out at 15 sites up- and downriver from dams during the 2019 dry season. We captured a total of 4,330 individual fish belonging to three orders, nine families and 26 species (and a hybrid individual). Electrical conductivity and pH were affected by the presence of dams and the distance from headwaters. Species richness and abundance did not vary in response to environmental variables. While species richness showed no significant variation along the sampled river section, abundance showed a negative relationship with distance from headwaters. Species composition varied significantly in response to pH, linear spatial factors and the presence of dams. Our results suggest that change in species composition of small-sized fish assemblages in the upper Branco River occurs due to variation in water characteristics, inherent dispersal limitation, and in response to the presence of dams.

Landscape-scale patterns in plant species richness along an arctic river

1997 ◽  
Vol 75 (10) ◽  
pp. 1748-1765 ◽  
Author(s):  
William A. Gould ◽  
Marilyn D. Walker
Keyword(s):  
Species Richness ◽  
Plant Species ◽  
Soil Ph ◽  
Environmental Heterogeneity ◽  
Landscape Heterogeneity ◽  
Vascular Plant ◽  
Plant Species Richness ◽  
The North ◽  
Environmental Controls ◽  
July Temperature

We examined relationships of vascular plant species richness with mean July temperature and components of landscape heterogeneity to determine the relative influence of temperature and the physical landscape on plant richness along the north-flowing Hood River in the Northwest Territories of Canada. We also examined variations in the composition of the flora to better understand the relationship between riparian gradients, environmental controls, environmental heterogeneity, and species richness. The vascular flora for the area studied includes 210 species. Richness at 17 sites along the river ranged from 69 to 109 species within 2400-m2 sample areas. Sites with the lowest richness were those in the upper reaches of the river, with richness generally increasing downstream. Variation in richness along the river is correlated with increasing environmental heterogeneity (r2 = 0.598, P = 0.0003), calculated as an index summarizing the range of site-level variation in a set of components including substrate type and texture, topographic variation (slope and aspect), relative surface area, substrate moisture, and soil pH. The most significant component of the index is an increase in the range of soil pH. Soil pH tends to increase downstream, and average site soil pH is the single best predictor of species richness (r2 = 0.857, P < 0.0001). The primary cause of higher soil pH is the presence of uplifted marine sediments, and tills derived from nonacidic Precambrian rock common along the lower river. Key words: species richness, arctic, riparian, pH, mean July temperature, environmental heterogeneity.

scholarly journals Vascular plant species richness in Alaskan arctic tundra: the importance of soil pH

2000 ◽  
Vol 88 (1) ◽  
pp. 54-66 ◽  
Author(s):  
Laura Gough ◽  
Gaius R. Shaver ◽  
Jenny Carroll ◽  
Dana L. Royer ◽  
James A. Laundre
Keyword(s):  
Species Richness ◽  
Plant Species ◽  
Soil Ph ◽  
Vascular Plant ◽  
Arctic Tundra ◽  
Plant Species Richness ◽  
Vascular Plant Species ◽  
Alaskan Arctic

Vegetation of inselbergs in Zimbabwe

1998 ◽  
Vol 55 (2) ◽  
pp. 267-293 ◽  
Author(s):  
R. Seine ◽  
U. Becker ◽  
S. Porembski ◽  
G. Follmann ◽  
W. Barthlott
Keyword(s):  
Species Richness ◽  
Vegetation Cover ◽  
Vascular Plants ◽  
Vascular Plant ◽  
Floristic Composition ◽  
Lichen Species ◽  
Rock Outcrops ◽  
Sparse Vegetation ◽  
First Time

Inselbergs are rounded rock outcrops, usually of Precambrian age, with sparse vegetation cover. The vegetation of inselbergs in Zimbabwe is described for the first time, based upon data sampled from 53 localities. Inselbergs support a range of habitats whose vegetation is described. Data on species richness and floristic composition of the inselberg flora (549 vascular plant, 25 bryophyte and 136 lichen species) are presented. Phytogeography and diversity of inselberg vegetation are discussed. First records for Zimbabwe are reported in lichens and vascular plants.

scholarly journals The species richness of the flora of selected sections of the Mietiułka river in the Polesie National Park

2012 ◽  
Vol 63 (2) ◽  
pp. 57-67
Author(s):  
Magdalena Pogorzelec
Keyword(s):  
Species Richness ◽  
Species Composition ◽  
Aquatic Plants ◽  
National Park ◽  
Vascular Plant ◽  
Ecological Groups ◽  
Environmental Evaluation ◽  
As Species ◽  
Sagittaria Sagittifolia ◽  
Water Dropwort

The aim of the study was to conduct an environmental evaluation of 6 selected sections of the improved Mietiułka River, which included an inventory and analysis of the vascular flora associated directly with this watercourse. The results of the study have shown that the flora of the study area is diverse in taxonomic, syntaxonomic and ecological terms, and that it comprises both typical aquatic plants and species characteristic of the habitats surrounding the river. In the flora found in the study sectors, a total of 114 vascular plant species was identified, which come from 42 botanical families, 15 syntaxonomic classes and belong to different ecological groups. Hemicryptophytes, spontaneophytes, species neutral to continentality as well as species included in the phytochorion with boreal elements: Euro-Siberian subelement, were clearly predominant in the species composition of the flora of all the study sectors. The macrophytes commonly found in Poland had the largest proportion. One species with a small number of stands in the country - water dropwort (<i>Oenanthe fistulosa</i>) - as well as two species threatened with extinction, <i>Sagittaria sagittifolia</i> and <i>Hypochoeris glabra</i>, were recorded.

scholarly journals On the calculation of the topographic wetness index: evaluation of different methods based on field observations

2006 ◽  
Vol 10 (1) ◽  
pp. 101-112 ◽  
Author(s):  
R. Sørensen ◽  
U. Zinko ◽  
J. Seibert
Keyword(s):  
Species Richness ◽  
Soil Moisture ◽  
Soil Ph ◽  
Groundwater Level ◽  
Vascular Plant ◽  
Plant Species Richness ◽  
Topographic Wetness Index ◽  
Wetness Index ◽  
Forest Sites ◽  
The Way

Abstract. The topographic wetness index (TWI, ln(a/tanβ)), which combines local upslope contributing area and slope, is commonly used to quantify topographic control on hydrological processes. Methods of computing this index differ primarily in the way the upslope contributing area is calculated. In this study we compared a number of calculation methods for TWI and evaluated them in terms of their correlation with the following measured variables: vascular plant species richness, soil pH, groundwater level, soil moisture, and a constructed wetness degree. The TWI was calculated by varying six parameters affecting the distribution of accumulated area among downslope cells and by varying the way the slope was calculated. All possible combinations of these parameters were calculated for two separate boreal forest sites in northern Sweden. We did not find a calculation method that performed best for all measured variables; rather the best methods seemed to be variable and site specific. However, we were able to identify some general characteristics of the best methods for different groups of measured variables. The results provide guiding principles for choosing the best method for estimating species richness, soil pH, groundwater level, and soil moisture by the TWI derived from digital elevation models.

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