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Survival of an endangered orchid Liparis loeselii in habitats with different water level fluctuations

100%

Megre D., Roze D., Dokane K., Jakobsone G., Karlovska A.

Polish Journal of Ecology

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2018

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tom 66

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nr 2

Liparis loeselii (L.) Rich. is an endangered orchid species which occurs in wetland habitats. For successful conservation of this orchid it is necessary to recognize its adaptive traits and special habitat requirements. Therefore, we examined morphological and anatomical traits in relation to the water level, cover of vascular plants and seed viability of L. loeselii in habitats with different water level fluctuations. Field studies of L. loeselii were carried out in nine localities and four habitat types: alkaline fen, calcareous fen with Cladium mariscus, transition mire and quaking bog. The fluctuations of seasonal water level were defined in the range from dry substrate to short time flooding (up to two weeks). Leaf length and width of 30 flowering specimens of L. loeselii as well as angle between the leaf blade and the axis of the inflorescence were measured at each locality. Seed viability and root anatomy were examined in the laboratory. The leaf angle was significantly affected (P < 0.05) by water level in the studied habitat. The leaf length to width ratio in each population of L. loeselii did not show significant differences between the years, but was characteristic for the habitat type. L. loeselii sensitivity to the long-term flooding in the habitat is associated with a lack of aerenchyma in its roots. During short-term flooding specimens of L. loeselii can survive due to a shallow root system and hyponastic leaf movements. As evidenced by seed viability, the most favourable growth conditions for L. loeselii are in the habitats with partially water saturated substrate with balanced water supply.

2

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Changes in the quality of water in Brdowskie Lake in 1997-2006

84%

Staniszewski R., Szoszkiewicz J.

Journal of Elementology

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2010

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tom 15

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nr 4

705-712

Most lakes in Poland are shallow and vulnerable to degradation mostly due to lake morphology and landscape structure. Other factors, like discharged sewage, internal loading and human activities in the watershed are also important. During studies on Brdowskie Lake, water samples were taken twice a year (spring and summer season) from the surface layer and analyses of soluble reactive phosphates, total phosphorus, nitrates, conductivity, five-day biochemical oxygen demand, chlorophyll a, dry mass of seston and Secchi depth were undertaken. Brdowskie Lake is situated in Kujawskie Lakeland and its catchment basin covers about 155.3 km2. The littoral vegetation is dominated by reed bed with a minor presence of other taxa. The lake is very susceptible to degradation (morphology, agricultural lands, housing) and has several potential sources of pollution, e.g. Noteæ River, a nameless stream and summer houses. In general, water quality of the lake was better during the spring season, especially in terms of chlorophyll a and dry mass of seston concentrations. In 1997- -2006, the level of conductivity was very changeable with the maximum values observed in 1999-2001. Significant correlations between some parameters in certain seasons of the year were found, e.g. between chlorophyll a and Secchi depth during spring and total phosphorus and phosphates in summer. The impact of water level fluctuations on water quality parameters, like total phosphorus and chlorophyll a was observed. According to the results, the quality water in Brdowskie Lake is improving. After a biological wastewater treatment plant in the catchment had opened, the rate of salts flowing into the lake with sewage was reduced.

3

Comparative effects of aquaculture and water level fluctuations on macroinvertebrate communities in Three Gorges Reservoir, China

84%

Chi S., Zheng Z., Zhang Z., Hu J., Zheng J., Zhao X., Hu J., Dong F., Peng J.

Polish Journal of Ecology

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2017

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tom 65

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nr 4

In this study, the comparative effects of the two disturbances (aquaculture and water level fluctuations) on macroinvertebrate communities were explored in two waterbodies connected with the reservoir system of Three Gorges Reservoir (TGR) in China. One water body called Gaoyang Bay which suffered organic pollution from intensive aquaculture. Another named Hanfeng Lake, where the effects of water-level fluctuations are obvious. The results showed that aquaculture could significantly affect the chemical forms of nutrients, decrease the α-diversity and increase the β-diversity of macroinvertebrates although the communities in the treatment area in Gaoyang Bay were not fundamentally changed comparing to the control area in the same bay. The densities of macroinvertebrates in the treatment area were significantly lower than that of the control area. The composition of functional feeding groups in the treatment area was close to that in Hanfeng Lake, but obviously different from that in the control area in Gaoyang Bay and the collectors and predators dominated the communities in this control area with the highest percentages. Although water-level fluctuations had negative effects on the communities by decreasing the α-diversity and increasing the β-diversity, which were confirmed by the values of Simpson index, Shannon-Wiener index and Harrison's index in the control area of Gaoyang bay and Hanfeng Lake, the adverse effects were relative low compared to aquaculture. In the bays of TGR, the small-scale disturbance (aquaculture activities) had more significant negative effects compared to the big-scale disturbance (water-level fluctuations related to dam operation of TGR).

4

Effect of long-term winter flooding on the vascular flora in the drawdown area of the Three Gorges Reservoir, China

84%

Wang Q., Yuan X., Liu H., Zhang Y., Cheng Z., Li B.

Polish Journal of Ecology

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2012

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tom 60

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nr 1

The dam construction and water impoundment have extensively altered flow regime and riparian ecosystems. However, the effect of long-term winter flooding of reservoir on plants of drawdown area is poorly known. The Three Gorges Dam in China, the largest dam in the world, created a drawdown area of 348.93 km2 between 145 m and 175 m above sea level around its reservoir. The drawdown area was submerged for more than half year in winter and exposed in summer. In the summer of 2009, the vegetation of fourteen sites in the drawdown area was investigated to determine the impact of winter flooding on vascular flora and to explore flood-tolerant species for vegetation reconstruction. One hundred and seventy five species of 58 families were recorded in present work，which indicated that 55% of vascular flora species disappear or became rare. The number of perennial species decreased to 50%. Therophytes, with 87 taxa, were the dominant life form. Strictly aquatic species were rather scarce for summer drought. Mean vegetation cover in the drawdown area was more than 70%. Species richness and vegetation cover along the elevation gradient exhibited a negative pattern correlated with flooding duration. The remarkable reduction of plant richness, variation of life form composition and alternation of dominant species indicated the strong influence of long-term winter flooding on vascular flora. Cynodon dactylon and Cyperus rotundus was highly resistant to long-term winter flooding and summer drought. Eight hardwoods (Vitex negundo, Morus alba, Sapium sebiferum, Glochidion puberum, Rhus chinensis, Melia azedarach, Pterocarya stenoptera and Trema levigata) exhibited high tolerance to winter flooding and may be potential candidates for vegetation restoration.

5

Dynamics of algal community changes in a short-lived periodical reservoir located in Lower Vistula River Valley

84%

Paczuska B.

Oceanological and Hydrobiological Studies

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2007

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tom 36

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nr Suppl.1

6

Habitat heterogeneity and biodiversity in the shore zone of water bodies

84%

Pieczynska E.

Acta Hydrobiologica

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1995

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tom 37

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nr Suppl.1

7

Reconstruction of wetland zones: physiological and biochemical responses of Salix variegata to winter submergence — a case study from water level fluctuation zone of the Three Gorges Reservoir

67%

Miao L., Xiao F., Xu W., Yang F.

Polish Journal of Ecology

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2016

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tom 64

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nr 1

The Salix variegata Franch. seedlings planted in the Three Gorges Reservoir (TGR) water level fluctuation zone (WLFZ) could survive after experiencing several seasons of winter submergence. We investigated the recovery mechanisms of S. variegata seedlings planted at the elevation of 168 m and 172 m in the TGR WLFZ after winter submergence. The results indicated that winter submergence caused some impacts on S. variegata seedlings with increases of hydrogen peroxide (H₂O₂), superoxide anions radical (O₂⁻˙), and malondialdehyde (MDA) levels, and decreases of antioxidant enzymatic systems during recovery stage after winter submergence. However, further analyses of relative water content (RWC), pigment content, proline content, carbohydrate content and several other antioxidant enzymatic activities (catalase (CAT), guaiacol peroxidase (G-POD), and glutathione peroxidase (GSH-POD)) showed that S. variegata seedlings were well recovered after winter submergence. These results indicate that S. variegata possesses strong winter submergence tolerance and adaptation to the specific hydrological environment in the TGR WLFZ. Therefore, S. variegata should be popularized as native tree species during the revegetation in the TGR WLFZ.

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Investigating the recent drought effects on underground water resources in the province of Kurdistan from a quantitative and qualitative point of view (Case study: Dehgolan and Ghorveh plains)

67%

Bashiri E., Bashiri J., Karimi F.

International Letters of Natural Sciences

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2013

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tom 03

The Ghorveh plain with an annual average rainfall of 350 millimeter and a cold and semi humid climate is located between the Dehgolan's watersheds and Chahardoli and 95 kilometers east of Sanandaj and northwest of Hamadan. From a geographic coordinates point of view it is situated between the longitudes of 47° 38' 52" to 48° 06' 03" eastern and latitudes of 35° 02' 22" to 35° 30' 54" northern . This plain leads to Mts. Darvazeh and Ebrahim Attar from south, it leads to hillside lands from the northern side , from Westside it reaches Mt. Bikheir and from the eastern part it is limited to the Dam Gaz heights. The area of the Ghorveh watershed is 1063/50 square kilometers while the area of the region under study is 197 square kilometers. Geologically speaking, it is located in the Sanadaj –Sirjan zone. The collision depth to the underground waters in the heights range bordering the plain is a maximum of 42 meters while the same rate about the river Talvar is at least zero and it is less than 5 meters in a wide range region of the eastern side of the plain. The direction of the underground water flow in the Ghorveh region is from the south west to north east. The Piezometrical water level changes compared to the western side plain has had a reduced height.The Dehgolan's plain with an annual average rainfall of 354 millimeters and a cold and semi humid climate is located in the eastern side of the city of Sanandaj between the longitudes of 47° 08' 00" to 48° 12' 00" eastern and latitudes of 35° 00' 00" to 36° 00'00" northern. This plain is limited to not very high ridge of Shanooreh from the eastern side and it leads to the Darband Kabood heights and Abdulrahman heights from south, while it leads to Mt. Sheida and Akhikamal and Salarabad from north and then it is limited to the Khatoon heights from the west part . The area of the watershed of Dehgolan is 2250 square kilometer and the area of the region under study is 644 square kilometers . Geologically and regionally speaking, it is part of the geological – structural zone of Sanandaj – Sirjan. The general slope of the region is towards east and north east. The main river of this plain is called Talvar. The alluvial aquifer of the Dehgolan's plain is of a free type and is on average 90meters thick where in some parts thickness swells to 90 meters.

9

Ecotones and hydrology: key conditions for fish in large rivers

67%

Schiemer F., Keckeis H., Flore L.

International Journal of Ecohydrology and Hydrobiology

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2001

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tom 01

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nr 1-2

10

The fluctuations of water level in the Odra Estuary

59%

Wisniewski B., Wolski T., Kowalewska-Kalkowska H.

Baltic Coastal Zone. Journal of Ecology and Protection of the Coastline

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2000

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tom 04

The work presents the results of studies on hydrological and meteorological determination of water level fluctuations in the Odra Estuary. Firstly there has been found the evident continuous increase of average water level at the gauge Swinoujscie from the beginning of observational series (1811) due to eustatic changes and gradual land decreasing. Next the study revealed that seasonal fluctuations of sea level are determined by the quantity of sea basin filling which is dependent on circulation conditions. Then examined storm surges (1993-1995) emphasised the important role of sea surface distortion caused by the dynamical movement of low-pressure system. Finally there was found that circulation conditions modify relations between water discharge of the Lower Odra River and water level differences data as measured at the coastal stations of the Szczecin Lagoon and the Swina Strait. Especially during the Odra flooding events there were found statistically significant relations between them.

Ograniczanie wyników

Survival of an endangered orchid Liparis loeselii in habitats with different water level fluctuations

Changes in the quality of water in Brdowskie Lake in 1997-2006

Comparative effects of aquaculture and water level fluctuations on macroinvertebrate communities in Three Gorges Reservoir, China

Effect of long-term winter flooding on the vascular flora in the drawdown area of the Three Gorges Reservoir, China

Dynamics of algal community changes in a short-lived periodical reservoir located in Lower Vistula River Valley

Habitat heterogeneity and biodiversity in the shore zone of water bodies

Reconstruction of wetland zones: physiological and biochemical responses of Salix variegata to winter submergence — a case study from water level fluctuation zone of the Three Gorges Reservoir

Investigating the recent drought effects on underground water resources in the province of Kurdistan from a quantitative and qualitative point of view (Case study: Dehgolan and Ghorveh plains)

Ecotones and hydrology: key conditions for fish in large rivers

The fluctuations of water level in the Odra Estuary