Effect of the Gabčíkovo Waterworks (Slovakia) on riparian floodplain forest ecosystems in the Danube inland delta: vegetation dynamics and trends

Biologia ◽  
2017 ◽  
Vol 72 (7) ◽  
Author(s):  
Mária Petrášová-Šibíková ◽  
Igor Matečný ◽  
Eva Uherčíková ◽  
Peter Pišút ◽  
Silvia Kubalová ◽  
...  

AbstractHuman alteration of watercourses is global phenomenon that has had significant impacts on local ecosystems and the services they provide. Monitoring of abiotic and biotic changes is essential to mitigating long-lasting effects, and the 23-year dataset from the Gabčíkovo Waterworks provided a rare opportunity to assess the impact of groundwater regimes on vegetation. The main aim of this study was to describe the effect of the Gabčíkovo Waterworks on vegetation structure and species composition of the adjacent riparian floodplain forests over the past 23 years. The results are based on studies of three permanent monitoring plots (PMPs) located in the Danube inland delta – two outside (PMP 1 and 3) and one (PMP 2) fully under the influence of the artificial supply system. Our results demonstrate that the Danube inland delta was negatively affected by the Gabčíkovo construction, particularly for sites outside of the artificial supply system. There was a significant decrease in soil moisture and increase in nitrogen at both external PMPs (1 and 3). Alter soil conditions were accompanied by negative changes in plant species composition demonstrated by decreases in the number of typical floodplain forest species that are characteristic for the alliance

2018 ◽  
Vol 10 (9) ◽  
pp. 3153
Author(s):  
Ditmar Kurtz ◽  
Marcus Giese ◽  
Folkard Asch ◽  
Saskia Windisch ◽  
María Goldfarb

High impact grazing (HIG) was proposed as a management option to reduce standing dead biomass in Northern Argentinean (Chaco) rangelands. However, the effects of HIG on grassland diversity and shifts in plant functional groups are largely unknown but essential to assess the sustainability of the impact. During a two-year grazing experiment, HIG was applied every month to analyze the seasonal effects on plant species composition and plant functional groups. The results indicate that irrespective of the season in which HIG was applied, the diversity parameters were not negatively affected. Species richness, the Shannon–Wiener diversity index and the Shannon’s equitability index did not differ from the control site within a 12-month period after HIG. While plant functional groups of dicotyledonous and annual species could not benefit from the HIG disturbance, C3-, C4-monocotyledonous and perennials increased their absolute and relative green cover. Our results suggest that HIG, if not applied in shorter frequencies than a year, neither alters diversity nor shifts the plant species composition of the grassland plant community, but instead it promotes previously established rather competitive species. HIG could therefore contribute as an alternative management practice to the sustainable land use intensification of the “Gran Chaco” grassland ecosystem and even counteract the encroachment of “low value” species.


10.12737/3822 ◽  
2014 ◽  
Vol 9 (1) ◽  
pp. 112-116
Author(s):  
Жубрин ◽  
Denis Zhubrin ◽  
Сабиров ◽  
Ayrat Sabirov

Conducting soil studies are relevant in determining the subordination of forest types and biodiversity of vegetation to soil taxa, in determining the dependence of basic forest stand productivity from soil conditions, in creating a land registry and economic assessment of forest land, in studying the soil evolution of forest plantations under the impact of anthropogenic influences. Soil is the most important environmental factor in shaping the productivity and biodiversity of forest phytocenosis. The study of forest soils is also important in terms of basic research of their genesis, evolution. The article presents the results of research of soil conditions of vegetation growth of forest ecosystems of northern regions of Volga of the Republic of Tatarstan. The main types of forest soils are characterized in the paper. The studied forest formations grow on various soils on genesis and forest vegetation properties: sod-podzol, gray forest, brown forest, brown forest sandy, alluvial meadow, rendziny soil. The granulometric structure of soils varies from sandy to the clay. The well structured soils are formed on loamy layers under forest phytocenosis canopy. Pine and spruce ecosystems have a medi-decomposed litter of moder and multi-moder types; linden, oak, birch and aspen biogeocoenoses have strong-decomposed litter of multi type, that characterizes the intense biological cycle of substances in forest ecosystems. The wide range of place conditions of territories causes the biological diversity of forest vegetation at the level of species and ecosystems.


2016 ◽  
Vol 47 (2) ◽  
pp. 115 ◽  
Author(s):  
Christiana Ndidi Egbinola

The study investigated the tree species composition along the forest-savanna boundary in Oyo state of Nigeria with the aim of assessing the impact of human activities on the floristic composition. A transect was placed along the study area and species data was collected from quadrats placed in study plots within different study sites. Detrended Correspondence Analysis (DCA) was used to determine vegetation assemblages, while both correlation and the analysis of variance (ANOVA) were used to show the relationship between species in the different study sites. Results of the DCA revealed three species assemblages, an area with only forest species, another with only savanna species and a third with both forest/savanna species. ANOVA results further revealed that within the forest and savanna assemblages, species in mature and successional sites were alike. The study therefore revealed that human activities’ within the region is leading to the establishment of savanna species and an elimination of forest species.


Hacquetia ◽  
2018 ◽  
Vol 17 (2) ◽  
pp. 163-169 ◽  
Author(s):  
Denisa Bazalová ◽  
Katarína Botková ◽  
Katarína Hegedüšová ◽  
Jana Májeková ◽  
Jana Medvecká ◽  
...  

Abstract Replacing native forests by alien tree plantations can lead to changes in the species composition of the understory. However, differences in the understory species spectrum can also be a part of the natural variability of forest stands. We have tested the suitability of the twin plots method for an evaluation of the impact of alien trees on the species composition of the understory. This research was conducted on an alluvial plain (SW Slovakia) that was originally covered by a hardwood floodplain forest. The study was based on 7 twin plots of black locust (Robinia pseudoacacia) and native forest plots, with a maximum distance of 100 meters between the members of the twins. The dissimilarity of the plots within the black locust forest was significantly lower than the dissimilarity between the twin plots. In addition, the dissimilarity of the plots within the hardwood floodplain forest was also significantly lower than the dissimilarity between the twin plots. Under the same environmental conditions, the higher dissimilarity of the twin plots was caused by major edificators and their impact on the understory vegetation. The twin plots method proved to be a suitable tool for analyses of the impact of alien trees on understory vegetation.


2020 ◽  
Author(s):  
Natalia Kowalska ◽  
Georg Jocher ◽  
Ladislav Šigut ◽  
Marian Pavelka

<p>Since the eddy covariance (EC) method became a key method for measurements of the energy and greenhouse gas exchange between ecosystems and the atmosphere, a large number of studies was conducted to understand the mechanisms driving the carbon exchange in forest ecosystems. In recent years, case studies further focused on testing and validating the applicability of the EC technique above forest ecosystems, also assessing the spatial and temporal variability of sub canopy fluxes. These studies led to the conclusion that there is a high probability of overestimating the forest carbon sink strength with EC measurements above the forest canopy only, as these measurements may miss respiration components from within and below the canopy due to insufficient mixing across the canopy. Additional below canopy EC measurements were suggested to tackle this problem and to get information about potential decoupling between below and above forest canopy air masses as well as potentially missing respiration components in the above canopy derived signal.</p><p>The overall goal of the study here is to derive an as detailed as possible understanding of the carbon exchange in Lanžhot floodplain forest with the help of concurrent EC measurements below and above the forest canopy. Lanžhot floodplain forest is situated 6.5 km north of the confluence of the Morava and Thaya rivers in Czech Republic (48.6815483 N, 16.9463317 E). The long-term average annual precipitation at this site is around 517 mm and the mean annual temperature is 9.5 °C. The average groundwater level is -2.7 m. Since a long time flooding occurs here very rarely, the last flooding event was in 2013. In addition, the site is hydrologically managed. Consequently, the water regime of the site changed over the years and represents nowadays relatively dry conditions for such type of ecosystem.</p><p>To reach our research goal we evaluate different single- and two-level filtering strategies of the above canopy derived carbon exchange values and the impact of these filterings on the annual ecosystem carbon exchange rates. Our hypothesis is that conventional single-level EC flux filtering strategies like the u<sub>*</sub>-filtering might not be sufficient to fully capture the carbon exchange of the studied floodplain forest ecosystem. We further hypothesize that additional below canopy EC measurements are mandatory to achieve unbiased forest carbon exchange values with the EC technique.</p>


Oryx ◽  
2012 ◽  
Vol 46 (3) ◽  
pp. 414-422 ◽  
Author(s):  
Brian D. Gerber ◽  
Sarah M. Karpanty ◽  
Johny Randrianantenaina

AbstractForest carnivores are threatened globally by logging and forest fragmentation yet we know relatively little about how such change affects predator populations. This is especially true in Madagascar, where carnivores have not been extensively studied. To understand better the effects of logging and fragmentation on Malagasy carnivores we evaluated species composition, density of fossa Cryptoprocta ferox and Malagasy civet Fossa fossana, and carnivore occupancy in central-eastern Madagascar. We photographically-sampled carnivores in two contiguous (primary and selectively-logged) and two fragmented rainforests (fragments <2.5 and >15 km from intact forest). Species composition varied, with more native carnivores in the contiguous than fragmented rainforests. F. fossana was absent from fragmented rainforests and at a lower density in selectively-logged than in primary rainforest (mean 1.38±SE 0.22 and 3.19±SE 0.55 individuals km−2, respectively). C. ferox was detected in fragments <2.5 km from forest and had similar densities in primary and selectively-logged forests (0.12±SE 0.05 and 0.09±SE 0.04 adults km−2, respectively) but was absent in fragments >15 km from forest. We identified only two protected areas in Madagascar that may maintain >300 adult C. ferox. Occupancy of broad-striped mongoose Galidictis fasciata was positively related to fragment size whereas occupancy of ring-tailed mongoose Galidia elegans elegans was negatively associated with increasing exotic wild cat (Felis spp.) activity at a camera site. Degraded rainforest fragments are difficult environments for Malagasy carnivores to occupy; there is a need to prioritize the reconnection and maintenance of contiguous forest tracts.


Sign in / Sign up

Export Citation Format

Share Document