Wyniki wyszukiwania - Biblioteka Nauki

1

New sites for Isoetes echinospora [Isoetaceae] in the Pomeranian Lakes [NW Poland]

100%

Bociag K.

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nr 2

2

The impact of acidic organic matter on the diversity of underwater vegetation in soft water lakes

100%

Bociag K.

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nr 3

EN

This paper addresses underwater vegetation in soft water lakes which are influenced by the anthropogenic input of allochtonic dissolved organic matter (DOM) from drained bogs. The aim of this work is to test the hypothesis regarding the role of DOM in shaping the diversity of underwater vegetation. Large differences in underwater vegetation habitats, the limitation of their occurrence to increasingly shallower littoral (the depth of the lower limit of their occurrence decreased from 12 m up to 1 m) and the regression of underwater vegetation were observed in lake types ranging from oligohumic (median (Me) of DOC in water = 2.5 mg C dm-3) to polyhumic (Me of DOC = 35.6 mg C dm-3). The gradual simplification of internal plant patch structure occurred and the Shannon-Weaver diversity index decreased (Me 0.04 → 0.00). Fewer species were observed in the lakes (Me 9 → 2), and the underwater vegetation covered increasingly smaller areas. Species replacement did not occur and no invasive species appeared.

3

Populacja Iris sibirica (Iridaceae) koło wsi Jerzyska w Puszczy Łochowskiej (środkowo-wschodnia Polska)

63%

Bociag K. , Gbur E.

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nr 2

328-331

4

Ramienice (Characeae, Charophyta) jezior Wdzydzkiego Parku Krajobrazowego i jego otuliny (NW Polska)

63%

Gabka M. , Bociag K.

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nr 2

5

Nowe stanowisko Cypripedium calceolus (Cypripediaceae) na Pomorzu Gdańskim

63%

Bociag K. , Gbur E.

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nr 2

323-325

6

Rozmieszczenie ramienic (Characeae) na obszarach sandrowych Równiny Charzykowskiej (NW Polska)

63%

Bociag K. , Chmara R.

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nr 2

7

Rozmieszczenie rdestnic (Potamogeton; Potamogetonaceae) na Równinie Charzykowskiej (NW, Polska)

63%

Chmara R. , Bociag K.

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tom 14

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nr 2

8

Nowe stanowisko Rhizocarpon geographicum (Rhizocarpaceae) w Polsce północno-wschodniej

63%

Bociag K. , Gbur E.

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nr 2

345-347

9

Nowe stanowisko Carex parviflora (Cyperaceae) w Tatrzańskim Parku Narodowym (Karpaty Zachodnie)

63%

Bociag K. , Gbur E.

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nr 2

333-335

10

The disintegration of populations of underwater plants in soft water lakes enriched with acidic organic matter

63%

Szmeja J. , Bociag K.

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nr 2

EN

The characteristics of habitats, individuals and populations of four submerged macrophytes, Lobelia dortmanna L., Isoetes lacustris L., Sphagnum denticulatum Brid. and Fontinalis antipyretica Hedw., were studied in 12 soft water oligohumic lakes which had no inflow of allochtonic DOM and the DOC concentration in the water was <4.0 mg C dm-3 and 13 humic lakes enriched with allochthonous dissolved organic matter (DOM) from drained peat bogs and ranging in DOC water concentration from 4.1 to 44.0 mg C dm-3. The analyses of population disintegration were conducted basing on characteristics of individuals (size, habitat, fertility) and populations (aggregation density index, settlement index of the population area). The settlement index of the population area for Lobelia, Fontinalis, Isoetes, Sphagnum decreased from 8.4 to 6.2 g d.w. m-2, 4.6 to 0.01 g d.w. m-2, 85.4 to <0.001 g d.w. m-2 and 39.3 to 7.2 g d.w. m-2, respectively. Similar trends were observed in aggregation density. The general pattern of the disintegration of populations of these species was always similar. It was independent of the source macrophytes drew resources from or their susceptibility to environmental changes. Individuals began to be eliminated from the deep and central parts of the population area. The remainder of the populations, which persist in the shallowest, best-illuminated part of the area, are themselves endangered by disturbances caused by wavy motion. The only populations of submerged macrophytes which can survive in polyhumic lakes under such conditions are those which are resistant to disturbances common in the shallow littoral (Lobelia dortmanna, Fontinalis antipyretica).

11

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

63%

Bociag K. , Szmeja J.

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nr 4

12

Diagnoza jezior lobeliowych w zachodniej czesci Pojezierza Pomorskiego

51%

Banas K. , Bociag K. , Szmeja J.

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tom 46

83-105

13

Effect of light competition with filamentous algae on the population dynamics and development of the moss species Warnstorfia exannulata in a softwater lake

51%

Szmeja J. , Bociag K. , Mierdalski M.

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nr 2

EN

The effect of a massive bloom of filamentous algae on the long-term abundance dynamics of the moss Warnstorfia exannulata (B., S. & G.) Loeske was studied in an acidic lowproductivity lake in NW Poland. Individuals were counted on 4 experimental plots, 1 × 1 m each, at a depth of 2.5 m. The studies were conducted for 36 months, every 30 days, by SCUBA diving. Over the three years the seasonal changes in water pH, conductivity, HCO₃⁻ concentration, sediment hydration and pH were not statistically significant (P> 0.05), and light intensity was higher in winter than in summer. Over the three years 4 consecutive stages of population development were observed: regeneration, stabilisation of abundance (fluctuations), regression and repeated regeneration. These stages appeared and lasted at different temperatures and light intensity. The greatest monthly increase in abundance took place in summer and lasted until the beginning of autumn under conditions of high temperature and relatively low light intensity. Long-term abundance variations were strongly correlated with the appearance of filamentous algae, less strongly with the dynamics of the dominant species (Sphagnum denticulatum), and the least with water temperature, light intensity, water and sediment pH, conductivity and HCO₃⁻ concentration. As a result of a massive bloom of these algae, light intensity decreased in the water, Warnstorfia shed its leaves, and then the entire population disappeared. In winter that year it began to regenerate from vegetative propagules (leafless shoots), which were the remains of individuals growing before the filamentous algae appeared. In softwater lakes such massive algal blooms are a common phenomenon which limits light transmission to the substrate and as a result leads to changes in the submerged vegetation structure, especially that of bryophytes.

14

The disappearance of stonewort populations in lobelia lakes of the Kashubian Lakeland (NW Poland)

51%

Bociag K. , Rekowska E. , Banas K.

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nr 2