scholarly journals Phytosociological Data in Assessment of Anthropogenic Changes in Vegetation of Rzeszów Reservoir

2021 ◽  
Vol 13 (16) ◽  
pp. 9071
Author(s):  
Maria Ziaja ◽  
Tomasz Wójcik ◽  
Małgorzata Wrzesień
Keyword(s):  
Environmental Variables ◽  
Vegetation Type ◽  
Plant Distribution ◽  
Vegetation Types ◽  
Ellenberg Indicator Values ◽  
Indicator Values ◽  
Marsh Vegetation ◽  
Se Poland ◽  
Main Factor

Phytosociological research on aquatic and marsh vegetation was conducted in Rzeszów Reservoir (SE Poland): 134 relevés according to the Braun-Blanquet method were collected there in 2016 and compared to 91 relevés published in 1994 (225 relevés in total). Changes in vegetation type, diversity measures, species composition, and Ellenberg Indicator Values (EIVs) for light, moisture, reaction, and nitrogen were analysed. Over the 22 years (1994–2016), the greatest changes were noted in communities of the classes Lemnetea and Potametea and the alliance Salicion albae. The long-term observations demonstrated the disappearance of 14 phytocoenoses and the occurrence of 12 new ones. An expansion of marsh communities (Typhetum latifoliae, Typhetum angustifoliae, Glycerietum maximae, Leersietum oryzoidis) was noted, causing a decline of several species and vegetation types. According to canonical correspondence analysis (CCA), four environmental variables (light, moisture, nitrogen, and pH) were related to plant distribution. The strong disturbances reflected in intensive eutrophication were due to human activity, which is the main factor shaping the ecological succession and overgrowing of the reservoir.

scholarly journals Monitoring Selected Species of Mammals in Grand Teton National Park in 2001

2001 ◽  
Vol 25 ◽  
pp. 82-87
Author(s):  
Brian Miller ◽  
Hank Harlow
Keyword(s):  
National Park ◽  
Vegetation Type ◽  
Vegetation Types ◽  
Population Composition ◽  
Grand Teton National Park ◽  
Needed Information ◽  
Mammal Distribution ◽  
The Impact ◽  
Term Monitoring

Our objective is to establish a long-term monitoring project that will assess the abundance and densities of selected species of mammals at sites representing five defined vegetation types found in Grand Teton National Park. The term monitoring implies data collection over multiple years. Taking long term estimations of population composition before, during, and after biotic and abiotic changes provides needed information to assess the impacts of such changes and furnish useful options for management decisions. This standardized monitoring plan will provide information on small and medium-sized mammals that will (1) assess species use of habitat, (2) monitor changes in species composition as a result of environmental change, such as precipitation and temperature, (3) produce predictive models of small and medium-sized mammal distribution based on vegetation type, and (4) analyze the impact of wolf colonization on the mammal (and plant) community.

scholarly journals Changes in salt-marsh vegetation weakly affect top consumers of aquatic food webs

2020 ◽  
Author(s):  
Lafage Denis ◽  
Carpentier Alexandre ◽  
Sylvain Duhamel ◽  
Christine Dupuy ◽  
Eric Feunteun ◽  
...  
Keyword(s):  
Stable Isotopes ◽  
Salt Marsh ◽  
Salt Marshes ◽  
Vegetation Type ◽  
Site Effect ◽  
Salt Marsh Vegetation ◽  
Gut Content ◽  
Marsh Vegetation ◽  
Nitrogen Inputs

AbstractSalt marshes are under high, and increasing, anthropogenic pressures that have notably been reported to affect the diet of several fish species, probably resulting in nursery function alterations. Most of the previous studies in Europe were yet based on gut content analysis of fish, which can be considered a snapshot of immediate impacts of salt-marsh changes, and hardly of long-term effects of disturbances. In this study, we investigated the impact of vegetation type (resulting from both plant invasion and sheep grazing) by assessing trophic network (and especially fish diet and position) of different salt-marsh conditions. Replicated samples of basic sources (particular organic matter and microphytobenthos), dominant vegetation, potential aquatic and terrestrial prey and fish of 3 main species were taken during summer 2010 in two bays from Western France (Mont -Saint-Michel Bay and Seine Estuary) and analysed using C and N stable isotope compositions. All response variables tested (overall trophic organization, trophic niche and trophic position) provided consistent results, i.e. a dominant site effect and a weaker effect of vegetation type. Site effect was attributed to differences in anthropogenic Nitrogen inputs and tidal regime between the two bays, with more marine signatures associated with a higher frequency of flooding events. A second hypothesis is that E. acuta, which has recently totally replaced typical salt-marsh vegetation in Mont Saint-Michel Bay strongly impacted the nursery function. The trophic status of dominant fish species was unchanged by local salt-marsh vegetation, and considered consistent with their diet, i.e. high for predatory species (the sea bass Dicentrarchus labrax and the common goby Pomatoschistus microps) and lower for biofilm grazing species (the thinlip mullet Chelon ramada). This study finally highlights the relevance of stable isotopes analyses for assessing long-term and integrative effects of changes in vegetation resulting from human disturbances in salt marshes.HighlightsCross-ecosystem subsidies are of high functional importance, notably in salt marshesFish are vectors of exchanges, most European studies being based on their gut contentUsing stable isotopes we analysed the effect of surrounding vegetation on food websSurprisingly we found weak vegetation and strong site effects on all metricsNitrogen inputs, site accessibility and loss of nursery function can explain this factAbstract Figure

scholarly journals Precision of helicopter-based total-area counts of large ungulates in bushveld

Koedoe ◽  
2002 ◽  
Vol 45 (2) ◽  
Author(s):  
B.K. Reilly
Keyword(s):  
Vegetation Type ◽  
Monitoring And Evaluation ◽  
Common Species ◽  
Small Sample ◽  
Vegetation Types ◽  
Large Herbivore ◽  
Coefficients Of Variation ◽  
Annual Population ◽  
Small Sample Sizes

Precision in helicopter total-area counts in bushveld for a range of common species are evaluated. Counts were conducted on properties ranging in size from 250 ha to 10 000 ha as part of experiments on precision and power. Counts were conducted in three vegetation types: mopane veld, sourish mixed bushveld and arid bushveld. Scant regard is given to precision as a factor in large herbivore monitoring, with more effort often devoted to accuracy. Coefficients of variation varied from 3.2 % to 70.9 %. Median values are generally acceptable for the establishment of trends for long-term monitoring, but might be inadequate for annual population size monitoring and evaluation. A regression of all species and vegetation types by the standard error showed a significant correlation. Similar regressions were also developed for impala, kudu, warthog, and zebra. Regressions by vegetation type for mopane veld, sourish mixed bushveld, and northwest arid bushveld were also significant. However, the high correlation for some vegetation types might be an artifact of the small sample sizes.

Spatial Distribution of Sheep, Feral Goats and Kangaroos in Woody Rangeland Paddocks.

1996 ◽  
Vol 18 (2) ◽  
pp. 270 ◽  
Author(s):  
J Landsberg ◽  
J Stol
Keyword(s):  
Vegetation Type ◽  
New South ◽  
Ground Cover ◽  
Tree Cover ◽  
Vegetation Types ◽  
Vegetative Cover ◽  
Large Herbivores ◽  
Grazing Impacts ◽  
South Wales

The densities and distributions of sheep, kangaroos and feral goats were assessed from extensive dung surveys following dry, moderate and green seasons in three large paddocks in the wooded rangelands of north-westem New South Wales. Densities of sheep (21 9nanimals/km2) were around the long-term district average. Densities of goats (24 animals/km2) were often higher than sheep. Densities of kangaroos (1 1 animals/km2) were usually much lower than either sheep or goats. Animal density was usually related to vegetative cover (ground cover for sheep and kangaroos, shrub and tree cover for goats), but there were also differences among paddocks. Distribution of kangaroos showed the most differentiation according to vegetation type, with densities being consistently high on a small area of alluvial grassland and very low in the paddock with no alluvial plains and the lowest levels of ground cover. The distributions of sheep and goats were correlated in the dry season and both species showed similar ranges in preferences for different vegetation types. Of the large herbivores present in these woody rangelands, kangaroos were the most selective in terms of the vegetation types they grazed, and goats were the least selective. Because their grazing activities are focussed on alluvial grasslands, kangaroos have potential to degrade this locally uncommon vegetation type. However, the densities of kangaroos in other, more widespread, vegetation types were uniformly low. Goats were frequently the most abundant large herbivores present and were also the least selective. Therefore goats probably have the greatest potential for causing widespread grazing impacts across much of these woody rangelands.

Effect of altered snow conditions on decomposition in three subalpine plant communities

2014 ◽  
Vol 9 (8) ◽  
pp. 811-822 ◽  
Author(s):  
Miroslav Zeidler ◽  
Martin Duchoslav ◽  
Marek Banaš
Keyword(s):  
Soil Temperature ◽  
Vegetation Type ◽  
Vegetation Types ◽  
Snow Density ◽  
Cellulose Decomposition ◽  
Snow Properties ◽  
Melting Period ◽  
Spatio Temporal ◽  
Snow Conditions

AbstractSnow cover and its spatio-temporal changes play a crucial role in the ecological functioning of mountains. Some human activities affecting snow properties may cause shifts in the biotic components of ecosystems, including decomposition. However, these activities remain poorly understood in subalpine environments. We explored the effect of human-modified snow conditions on cellulose decomposition in three vegetation types. Snow density, soil temperature, and the decomposition of cellulose were studied in Athyrium, Calamagrostis, and Vaccinium vegetation types, comparing stands intersected by groomed ski slope and natural (outside the ski slope) stands. Increased snow density caused the deterioration of snow insulation and decreased the soil temperature inside the ski slope only slightly in comparison with that outside the ski slope in all vegetation types studied. The decomposition was apparently lower in Athyrium vegetation relative to the other vegetation types and strongly (Athyrium vegetation) to weakly lower (other vegetation types) in groomed than in ungroomed stands. Wintertime, including the melting period, was decisive for overall decomposition. Our results suggest that differences in decomposition are influenced by ski slope operations and vegetation type. Alterations in snow conditions appeared to be subtle and long-term but with important consequences for conservation management.

scholarly journals Monitoring Selected Species of Mammals in Grand Teton National Park in 2000

2000 ◽  
Vol 24 ◽  
pp. 60-65
Author(s):  
Brian Miller ◽  
Hank Harlow
Keyword(s):  
National Park ◽  
Vegetation Type ◽  
Vegetation Types ◽  
Population Composition ◽  
Grand Teton National Park ◽  
Needed Information ◽  
Mammal Distribution ◽  
The Impact ◽  
Term Monitoring

Our objective is to establish a long-term monitoring project that will assess the abundance and densities of selected species of mammals at sites representing five defined vegetation types found in Grand Teton National Park. The term monitoring implies data collection over multiple years. Taking long term estimations of population composition before, during, and after biotic and abiotic changes provides needed information to assess the impacts of such changes and furnishes useful options for management decisions. This standardized monitoring plan will provide information on small and medium-sized mammals that will (1) assess species use of habitat, (2) monitor changes in species composition as a result of environmental change, such as precipitation and temperature, (3) produce predictive models of small and medium-sized mammal distribution based on vegetation type, and (4) analyze the impact of wolf colonization on the mammal (and plant) community.

scholarly journals Site Characteristics More Than Vegetation Type Influence Food Web Structure of Intertidal Salt Marshes

2021 ◽  
Vol 8 ◽  
Author(s):  
Denis Lafage ◽  
Alexandre Carpentier ◽  
Sylvain Duhamel ◽  
Christine Dupuy ◽  
Eric Feunteun ◽  
...  
Keyword(s):  
Salt Marsh ◽  
Salt Marshes ◽  
Trophic Position ◽  
Vegetation Type ◽  
Sea Bass ◽  
Site Effect ◽  
Salt Marsh Vegetation ◽  
Seine Estuary ◽  
Marsh Vegetation

Salt marshes are under increasing anthropogenic pressures that have been reported to affect the diet of fish (e.g., change in prey composition and availability), eventually resulting in alterations in their nursery function. Most studies in Europe are based on fish gut content analysis, which only reflect a small proportion of pressures to salt marshes, and do not necessarily reflect long-term disturbances. In this study, we investigated the impact of salt-marsh vegetation type on trophic network structures (i.e., fish diet and trophic position). Primary producers (particulate organic matter, microphytobenthos, and dominant terrestrial plants), potential aquatic and terrestrial prey, and fish of two dominant species (sea bass and thinlip mullet) were sampled during the summer of 2010 in four creeks from two sites from Western France (the Mont-Saint-Michel Bay and the Seine Estuary). Analysis was undertaken using C and N stable-isotope compositions. Tested response variables (diet and trophic position) suggested a dominant site effect and a weaker effect of surrounding vegetation type. Site effect was attributed to differences in anthropogenic nitrogen inputs (with a steep increase in the Mont-Saint-Michel Bay) and tidal regime between the two bays, with more marine signatures associated with a higher frequency and duration of tidal flooding events in the Seine Estuary. A second hypothesis is that invasive Elytrigia acuta, which has recently replaced typical salt-marsh vegetation in Mont-Saint-Michel Bay, negatively impacted the native salt-marshes nursery function by modifying the access to terrestrial prey on this site. The trophic position of the sea bass and the thinlip mullet was unchanged by local salt-marsh vegetation, and considered consistent with their diet. This study highlights the relevance of stable-isotopes analyses for assessing long-term and integrative effects of changes in vegetation resulting from human disturbances in salt marshes.

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