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  1. 5 Polish Journal of Ecology

  2. 3 Acta Palaeobotanica

  3. 3 Acta Societatis Botanicorum Poloniae

  4. 2 Annals of Warsaw University of Life Sciences - SGGW. Land Reclamation

  5. 2 Biodiversity: Research and Conservation

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  1. 3 Sikorski P.

  2. 2 Hewelke P.

  3. 2 Sikorska D.

  4. 2 Szmeja J.

  5. 1 Angiel P.

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  1. 2 2015

  2. 1 2012

  3. 3 2011

  4. 2 2010

  5. 2 2009

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1

Vegetation change models in the riparian landscape of the Blankowa river valley (in north-east Poland)

100%
Sikorski P., Wysocki C., Pawlicki R.
Annals of Warsaw Agricultural University. Horticulture (Landscape Architecture)
|
2004
|
tom 25
2
Artykuł dostępny w postaci pełnego tekstu - kliknij by otworzyć plik
Content available

Protection of valuable water dependent ecosystems in urban areas

100%
Sikorska D., Sikorski P., Hewelke P.
Annals of Warsaw University of Life Sciences - SGGW. Land Reclamation
|
2010
|
tom 42
|
nr 2
Water dependent ecosystems are habitats most vulnerable to urbanization pressure. There are not many such habitats in Warsaw. Those which remained are mostly dewatered sites existing within green areas such as parks. Habitats with peat and moorsh soils have a unique value, thus there is a rational need for detailed research and evaluation to preserve them. This paper is a case-study of two different water dependent ecosystems, localized within the boundaries of Poland’s capital city, both remaining under strong urbanization pressure. Different actions were undertaken to preserve those habitats, with differing results. We examined tendencies of vegetation during recent 20–30 years, basing on fl oristical data. In the areas, where water regime has been disrupted, like Natural Landscape Complex “Olszyna” a significant decline of plants rare in the scale of Warsaw is being noticed. Habitats not disturbed by human interference like ”Zakole Wawerskie” do not suffer significant changes, even an increase of rare plants was marked. Presence of water dependent ecosystems is also correlated with population density. In the areas of highest population density these habitats occur seldom, are of a small size and have simplified border zones. The only areas within Warsaw borders where water dependent ecosystems maintained are the urban parks. In the last decades a progressive decline of wetlands is being noticed, which was also confirmed in this study. The only real chance for further preservation of this areas is to create biodiversity hotspots and good recreation infrastructure.
3

Changes in the vegetation of softwater lakes under the influence of humic substances

100%
Bociag K., Szmeja J.
Polish Journal of Ecology
|
2001
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tom 49
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nr 4
4

Eutrophication and acidification processes in habitats and vegetation changes in the Sudeten Mountains

100%
Fabiszewski J., Brej T.
Publications of the Department of Plant Taxonomy of the Adam Mickiewicz University in Poznan
|
2000
|
tom 10
5

Tendencies of changes in the flora and vegetation structure of Pomeranian lakes under the influence of humic substances

100%
Szmeja J.
Publications of the Department of Plant Taxonomy of the Adam Mickiewicz University in Poznan
|
2000
|
tom 10
6

Duration of vegetation disturbance in urban hydrogenic ecosystems due to drainage

84%
Sikorska D., Sikorski P., Hewelke P.
Annals of Warsaw University of Life Sciences - SGGW. Horticulture and Landscape Architecture
|
2009
|
tom 30
7

New localities of Orobanche bartlingii Griseb. in the Silesian-Cracow Upland as a result of the spread of Libanotis pyrenaica (L.) Bourg. due to the changes in land use

84%
Babczynska-Sendek B., Blonska A., Skowronek I.
Biodiversity: Research and Conservation
|
2015
|
tom 39
8

Species richness, biomass production and recent vegetation changes of Estonian floodplain grasslands

84%
Truus L., Puusild E.
Polish Journal of Ecology
|
2009
|
tom 57
|
nr 1
33-45
We studied vegetation diversity and standing biomass in relation to site moisture (moist, wet) and different management regimes (regularly mown (A), recently abandoned (B), un-mown for at least 15 years but with mowing re-introduced recently (C), and abandoned for at least 15 years without re-introduction of mowing (D)) on floodplain grasslands in Soomaa National Park, SW Estonia. A flexible quadrate size (area inhabited by 500 ramets) was used for the estimation of life-form distribution, species richness, ramet density and weight of standing biomass. The size of the actual species pool (Spool) was also estimated and relative richness (Srel500), mean plant unit area (PUA), plant unit biomass (PUB), ramet density per square metre and standing dry biomass per square metre were calculated. Additionally, changes in Estonian floodplain grassland vegetation between the 1960s and the 1990s were analysed by comparing the life-form distribution of frequent species on floodplain grasslands in the 1960s and 1990s. Life-form distribution depended both on moisture conditions and on the management regime. Tussock-forming graminoids dominated in regularly mown moist sites and long-term unmown wet sites, while mat-forming graminoids dominated in sites with irregular management. The proportion of herb ramets was highest in unmanaged moist sites without regular mowing. In general, the life-form composition of floodplain grassland flora has shifted from low-growing herbaceous plants to tall-growing herbaceous plants during the abandonment period (from 1960s to 1990s). The effect of site moisture on the standing biomass-species richness relation and PUA was not significant, but the effect of the management regime was notable. PUA varied tenfold (mean 2.6 cm² at moist sites with the management regime B but was 25.2 cm² at un-managed wet sites). Dry standing biomass varied threefold depending on the management regime (from 263 to 763 g m⁻²). Ramet density, PUA, PUB, Spool, and life-form distribution on plots with recently re-introduced mowing (regime C) differed significantly from those of plots with regime D but did not differ from regularly mown plots (regime A). Management cessation led to a change in life-form distribution. Dominance of certain lifeforms depended on site moisture but the most obvious change was the increase of vegetation height.
9

Vegetation mapping in Norway and a scenario for vegetation changes in a mountain district

84%
Bryn A.
Geographia Polonica
|
2006
|
tom 79
|
nr 1
10
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Content available

Hydrological background of the dune slack vegetation in the Kiskunság

84%
Margoczi K., Szanyi J., Aradi E., Busa-Fekete B.
Annals of Warsaw University of Life Sciences - SGGW. Land Reclamation
|
2007
|
nr 38
105-113
In the southern Kiskunság the natural vegetation (sand steppe, fen meadow, fen or marsh and alkali vegetation) survived in the dune slack meadows (DSM). The vegetation of these meadows are species rich, and has high natural value. The main goal of this study is to reveal the hydrological backgrounds in order to help conservation of the natural values. Two DSM was investigated (MM and CS site): vegetation was sampled, observation wells were planted, and data of other wells in similar position were used to describe the hydrological background of the vegetation. The characteristic groundwater level of the same vegetation type in the relatively wet 2005 year was higher in MM site, than in the CS site. We suppose, that this is a consequence of the earlier vegetation change because of the strong decrease of groundwater level in the region of MM site. The model of hydraulic fl ow system showed that the DSMs are situated in hydraulic discharge zones. We suppose, that an upward fl ow plays an important role in development of alkali vegetation in the CS site. Cross-correlation coeffi cient between groundwater and previous precipitation indicated a quick infi ltration of rainwater into the soil, and a pressure front of the groundwater stream reaching the area of well after 22–23 days after rainfall. The quick and strong regional hydrological changes, especially the decrease of groundwater level would endanger this valuable vegetation, but certain resistance and plasticity of it is rather possible.
11

Assessment of biodiversity in Molinia meadows in Kampinoski National Park based on biocenotic indicators

84%
Kacki Z., Michalska-Hejduk D.
Polish Journal of Environmental Studies
|
2010
|
tom 19
|
nr 2
351-362
Communities of purple moor-grass meadows are generally decreasing. Many important problems of classification and phytogeography are connected with them. The main goal of the present study was to evaluate changes in species diversity that took place after mowing of Molinion meadows in Kampinoski National Park was discontinued from 1993 to 2006. Selected Molinion meadows in the park were evaluated in terms of their biological diversity. The data collected represented meadows that were still maintained, as well as meadows that had been abandoned at different times in the past. Biodiversity was evaluated using standard ecological indices and Disturbance Index (Z). In general, the Disturbance Index showed an increase in plant community forms that were abandoned or invaded by alien species. An association that was most like the typical form was seen in well maintained meadows, which suggests that the Disturbance Index continually rises with time after a meadow is abandoned. Ecological strategies and mowing tolerance were determined with the help of the BIOLFLOR database. Numerical classification revealed a highly diverse pattern of variability in the meadows examined. Correlations between ecological indicators and phytocenotic variability in Molinion meadows were also evaluated. Unmanaged meadows were compared to meadows in which meadow conservation management practices were carried out.
12

Changes in the vegetation of "Wrzosiec" mire in 1991-2009 (Western Pomerania)

84%
Popiela A., Fudali E., Lysko A.
Biodiversity: Research and Conservation
|
2011
|
tom 21
13

Changes in the area of protected plant communities in the middle Vistula River valley in the second half of the 20th century

84%
Kowalska A.
Polish Journal of Ecology
|
2012
|
tom 60
|
nr 1
This research sought to indicate changes in the area of plant communities designated for protection in part of the middle Vistula river valley. The study concerned the 50-year period 1949–2001, with the changes registered cartographically. The study area (about 905 km2) is located between the Sanna confluence above Annopol and Góra Kalwaria (from km 295 to km 482 of the river course). The analysis of changes determined the general trends of the natural environment transformation in the second half of 20th century that helped to indicate areas that should be protected additionally. Nineteen types of habitats listed in legal statutes (Habitats Directive etc.) were identified in the chosen part of the valley. Over 50 years, grassland communities have undergone the most significant modifications. Vegetation changes reveal a tendency of a lowering of the water level or a change in the horizontal movement of water as well as of aggradation (increased sediment accumulation) in the river-channel. There are indications that two specific areas should be protected additionally because of the definite presence of valuable natural habitats.
14
Artykuł dostępny w postaci pełnego tekstu - kliknij by otworzyć plik
Content available

Changes in vegetation and soil seed bank of meadow after waterlogging caused by Castor fiber

84%
Franczak M., Czarnecka B.
Acta Societatis Botanicorum Poloniae
|
2015
|
tom 84
|
nr 2
Soil waterlogging is among abiotic stresses that influence species composition and productivity in numerous plant communities. The aim of the study was to find answer to the question of how waterlogging caused by beavers’ activity induces quantitative and qualitative changes of vegetation and soil seed bank levels of variable-moist meadows. An immediate effect of the waterlogging at the level of vegetation was the decline in species richness and a decrease in the values of the biodiversity index. Water stress inhibited growth and development of plants already present and, primarily, impeded recruitment of new individuals of species characteristic of variable-moist meadows, e.g. Cirsium rivulare, Filipendula ulmaria and Lythrum salicaria, which were replaced by Carex acutiformis. Prolonged waterlogging did not induce equally substantial changes in the soil seed bank as in the vegetation. Both in the waterlogged and control patches, slightly decreased species richness and biodiversity index were recorded. After waterlogging withdrawal, the reserves of the soil seed bank were slightly higher than the initial values. The differences were not statistically significant. In the waterlogged patch, the qualitative floristic similarity between taxa identified in the soil seed bank and vegetation cover declined, which was evidenced by the value of Jaccard’s index decreasing from 0.46 to 0.36. A reverse relationship was found in control patch, where the value of the similarity index slightly increased from 0.41 to 0.48.
15

Changes in the vegetation of filamentous green algae in the Antoninek preliminary reservoir

84%
Dondajewska R., Frankowski T., Wojak P.
Oceanological and Hydrobiological Studies
|
2007
|
tom 36
|
nr Suppl.1
16
Artykuł dostępny w postaci pełnego tekstu - kliknij by otworzyć plik
Content available

Effect of ecological factors on the zonation of wetland vegetation

84%
Hrivnak R.
Acta Societatis Botanicorum Poloniae
|
2005
|
tom 74
|
nr 1
The influence of some ecological factors to aquatic and marsh vegetation was studied during 1998-2000. Three basic vegetation units (Caricetum buekii, Typhetum latifoliae and Ceratophylletum submersi) and three transitional communities were defined in the belt transect, which was established along the moisture gradient. The content of available soil nutrients in individual vegetation types differed only in case of the Ceratophyllum submersum community, where a higher magnesium and nitrogen content accumulated due to specific environmental conditions. Water and marsh vegetation is usually characterised by a pronounced spatial and temporal dynamics. In the studied area, its zonation was dependent from the terrain morphology, and both depth and duration of floods. The fluctuation of ground and surface water table during a three-year period caused changes in the occurrence and cover of several species (e.g. Carex buekii, Typha latifolia, aquatic macrophytes). Pronounced changes in the cover of some species occurred even within a single vegetation season due to the long-term sink of water table below the ground surface.
17

Post-Glacial vegetational changes in the Middle Roztocze [E Poland]

84%
Balaga K.
Acta Palaeobotanica
|
1998
|
tom 38
|
nr 1
18

An interstadial flora from the Zalesiaki locality near Dzialoszyn [Silesian-Cracovian Upland]

84%
Nita M.
Acta Palaeobotanica
|
1998
|
tom 38
|
nr 1
19

Forecasting carbon budget under climate change and CO2 fertilization for subtropical region in China using Integrated Biosphere Simulator (IBIS) model

67%
Zhu Q., Jiang H., Liu J., Peng C., Fang X., Yu S., Zhou G., Wei X., Ju W.
Polish Journal of Ecology
|
2011
|
tom 59
|
nr 1
The regional carbon budget of the climatic transition zone may be very sensitive to climate change and increasing atmospheric CO2 concentrations. This study simulated the carbon cycles under these changes using process-based ecosystem models. The Integrated Biosphere Simulator (IBIS), a Dynamic Global Vegetation Model (DGVM), was used to evaluate the impacts of climate change and CO2 fertilization on net primary production (NPP), net ecosystem production (NEP), and the vegetation structure of terrestrial ecosystems in Zhejiang province (area 101,800 km2, mainly covered by subtropical evergreen forest and warm-temperate evergreen broadleaf forest) which is located in the subtropical climate area of China. Two general circulation models (HADCM3 and CGCM3) representing four IPCC climate change scenarios (HC3AA, HC3GG, CGCM-sresa2, and CGCM-sresb1) were used as climate inputs for IBIS. Results show that simulated historical biomass and NPP are consistent with field and other modelled data, which makes the analysis of future carbon budget reliable. The results indicate that NPP over the entire Zhejiang province was about 55 Mt C yr-1 during the last half of the 21st century. An NPP increase of about 24 Mt C by the end of the 21st century was estimated with the combined effects of increasing CO2 and climate change. A slight NPP increase of about 5 Mt C was estimated under the climate change alone scenario. Forests in Zhejiang are currently acting as a carbon sink with an average NEP of about 2.5 Mt C yr–1. NEP will increase to about 5 Mt C yr–1 by the end of the 21st century with the increasing atmospheric CO2 concentration and climate change. However, climate change alone will reduce the forest carbon sequestration of Zhejiang’s forests. Future climate warming will substantially change the vegetation cover types; warm-temperate evergreen broadleaf forest will be gradually substituted by subtropical evergreen forest. An increasing CO2 concentration will have little contribution to vegetation changes. Simulated NPP shows geographic patterns consistent with temperature to a certain extent, and precipitation is not the limiting factor for forest NPP in the subtropical climate conditions. There is no close relationship between the spatial pattern of NEP and climate condition.
20

Changes in the flora and vegetation of the Torfowisko Rabien Reserve near Lodz [Poland], and their proposed conservation methods

67%
Kucharski L., Kurzac M., Rakowska B., Sitkowska M.
Nature Conservation
|
2004
|
tom 60
49-62
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