Wyniki wyszukiwania

1

The role of ecotones in man-disturbed landscape: boundaries between mixed forest and adjacent man-made ecosystems in the Kampinos National Park, Poland

100%

Dabrowska-Prot E., Wasilowska A.

Polish Journal of Ecology

|

2012

|

tom 60

|

nr 4

Ecologists agree that one of the main effects of human activity is the decrease in patch size in the landscape and hence an increase in ecotone length as a transition zone between adjacent ecological systems. Theoretical and practical importance of this concept has become one of the leading issues in current ecological research. The ecological importance of the ecotones was investigated, in the boundary of natural forest complex of the Kampinos National Park and adjacent anthropogenic ecosystems. Quantitative and qualitative changes of plant communities and of dipterans (Chloropidae) – important pests of wild and crop plants – were recorded along four types of transects located at the distance of 3 km: 1/ mixed forest (Querco roboris-Pinetum Mat. 1981) – ecotone – managed meadow (Deschampsietum caespitosae Hor vatic 1930); 2/ mixed forest – ecotone – crop field (Arnoserido-Scleranthetum R.Tx.1937); 3/ mixed forest – ecotone – spontaneously growing 20-year-old birch wood; 4/ mixed forest – ecotone – planted 17-year-old pine wood. The exchange of plant and dipteran species between forest ecosystem and its surrounding was analysed. The role of ecotones as transit zone or barrier for such exchange and as optimum or exclusive habitat for plant and dipteran associations was evaluated. Botanical studies showed that the neighbouring, ecotone-forming communities differed markedly in the vegetation structure and species composition (similarity index between them varied from 8 to 47%). Width of contact zones was also different, ranging from 4 to 14 m. Therefore, two groups of transects were distinguished: mixed forest – young woods and mixed forest – agricultural communities which differed in plant species richness and vegetation structure in particular transect zones. It created clear contrast between ecosystems and their ecotones. Some species were being found exclusively in ecotones but these species differed among different ecotones. The so-called ‘edge effect’ was manifested in increased number of plant species in the ecotone compared with neighbouring ecosystems, higher density of some populations and their better life condition (reflected in individual’s size, earlier entering subsequent phenological phases, fecundity). Chloropidae mainly dwelled the transect of mixed forest – meadow (60% of all caught in study area) and mixed forest – crop field (24%). Only 16% of dipteran species were caught in the transect of mixed forest – woods. Phytophagous species dominated in the first two transects (80–86% of the total number). Saprophagous species were 4–6 time less numerous there. The proportions of both trophic groups were more uniform in the transect of mixed forest – woods. Of the 44 Chloropidae species only 10 (22%) were widely dispersed in the study area and only two species – the dangerous pests Oscinella frit L. and O. pusilla Mg. were noted in all zones of all studied transects. In the transects of mixed forest and anthropogenicecosystems, only meadow and crop field created optimal habitats for Chloropidae They were ‘ecological traps’ that maintained over 66% of all dipterans caught in the study area. This finding contradicts the supposition of potential threat posed by these pests to protected forest grounds due to a proximity of nearby meadows and croplands. Similarly, there was no threat of penetrating the sustainable mixed pine forest complex by synanthropic plant species. They were mainly found in the crop field. Only 1/3 of these species permeated to the ecotone zone, but none to the forest.

2

Crustal structure of the continent-ocean transition zone along two deep seismic transects in north-western Spitsbergen

100%

Czuba W., Ritzmann O., Nishimura Y., Grad M., Mjelde R., Guterch A., Jokat W.

Polish Polar Research

|

2004

|

tom 25

|

nr 3-4

205-221

3

Location of the transition zone of the Barn Owl subspecies Tyto alba alba and Tyto alba guttata [Strigiformes: Tytonidae]

100%

Matics R., Hoffmann G.

Acta Zoologica Cracoviensia

|

2002

|

tom 45

|

nr 2

The colouration of the underparts of the Barn Owl ranges in Europe from reddish-brown to white. This character, that shows a clinal variation, is thought to be a marker of subspecies identity. The subspecific identity or transitional state of a total 64 Barn Owl Tyto alba pairs was determined on the basis of their phenotypic characteristics. The present authors investigated the breadth of the transition zone in Hungary on the basis of the distribution of the white-chested subspecies and the transitional phenotype, and it was found to be at least 500 km wide. The width of the transition zone may result from the lack of preferences in mating pair choice. The observed pattern of phenotypic distribution is due to the marginal location of the studied population in the transition zone.

4

Altitudinal variation in the diet of sika deer on the Izu Peninsula: patterns in the transitional zone of geographic variation along the Japanese archipelago

80%

Kitamura T., Sato Y., Takatsuki S.

Acta Theriologica

|

2010

|

tom 55

|

nr 1

89-93

Geographical variation in the diet of sika deer Cervus nippon Temminck, 1838 has been well characterised: northern populations are grazers, whereas southern deer are browsers. This variation largely reflects genetic-based differences in morphology. However, environmental factors would be also important. If a same genetic population live in different habitats, we can check altitudinal shifts in sika deer food consumption. We hypothesised that changes in the diet of the sika deer population on the Izu Peninsula, which is located within the transitional zone of resource (vegetation) variation and encompasses a broad altitudinal range, would mirror shifts in the composition of vegetation. Analyses of the rumen contents of the deer population indicated that dwarf bamboo accounted for 10.5, 46.2, and 74.3% of the deer diet in the low (<800 m), middle (800–1000 m), and high (>1000 m) altitudinal zones, respectively. In contrast, evergreen broad-leaved species accounted for 35.7, 23.1, and 5.9%, respectively. These results suggest that the diet of sika deer is more strongly affected by environmental factors, such as plant community composition, than by genetic factors.

5

Dynamics of sandy desertification and detection of sandy land-steppe boundary: vegetation and soil properties

80%

Xu D., Xu X., Xie Y., Wang K.

Polish Journal of Ecology

|

2012

|

tom 60

|

nr 2

Desertification is one of the most serious environmental problems on a global scale. China suffers from desertification over large areas. Landscape boundaries profoundly influence the structure and function of landscapes, and influence ecological processes both locally and over large scales. Data on soil properties and vegetation collected on three 110 km parallel transects across sandy land-steppe transition zone in Yanchi county, Ningxia region, northwestern China, were used to analyze changes along the sandy land/steppe boundary by using the Moving Split Window (MSW), to determine desertification dynamics, and to explore changes of vegetation and soil properties among different desertification degree. Combining the dissimilarity profiles of soil particle size with importance value (IV) of vegetation, four boundaries were detected along transects. According to the four boundaries, we divided the whole sandy land/steppe ecotone area into five desertification categories: potential desertification (PD), light desertification (LD), medium desertification (MD), severe desertification (SD) and extreme desertification (ED). Sand fractions increased, while silt and clay fractions, soil organic C, total N and available N decreased and exhibited clear gradient changes from the potential desertification land to the extreme desertification land. All areas we studied have been desertificated at different degree based upon soil particle compositions at different depths. With the aggravation of sandy desertification, the steppe species dominating in the potential desertification land gradually gave place to arid and sand tolerant perennials and therophytes and eventually to psammophyte annuals and shrubs in the extreme desertification land.

6

Artykuł dostępny w postaci pełnego tekstu - kliknij by otworzyć plik

Distribution of phytoplankton along the thermohaline gradient in the North-Eastern Adriatic channel; winter aspect

80%

Vilicic D., Kuzmic M., Bosak S., Silovic T., Hrustic E., Buric Z.

Oceanologia

|

2009

|

tom 51

|

nr 4

The distribution of phytoplankton and its relation to the hydrographic features in the north-eastern Adriatic was investigated in February 2008. The area of interest included a thermohaline gradient in the channel situated between the coast and the islands lying parallel to the coast. The gradient is controlled by the influx of oligotrophic karstic riverine water at the south-eastern end,subma rine springs in the middle part,an d warmer offshore waters at the north-western end of the channel. The change of temperature and salinity in the estuarine transition zone was accompanied by abundant diatoms and dinoflagellates below the halocline,with dominant chain-forming diatoms (Chaetoceros, Bacteriastrum) in abundances reaching 5×105 cells dm−3. The impact of coastal submarine springs detected by infrared remote sensing resulted in the growth of cyanobacteria in the nitrogen-depleted surface waters. The greater contribution of picoplankton, as well as of nanoplanktonic coccolithophorids and cryptophytes,in the outer channel system indicated their preference for oligotrophic conditions. Flow cytometric counts of nanophytoplankton were 10–30 times greater than inverted microscope counts. Cyanobacteria were about five times more abundant than picoeukaryotes. The study demonstrates how different techniques (remote sensing and in situ investigations) can be useful in understanding the biological and hydrographic set-up in the specific oligotrophic eastern Adriatic coastal environment.

7

The mosaic diversity of ground vegetation along the transect through the transition zone from the pure coniferous to the mixed coniferous site in the Bialowieza Primeval Forest in North-Eastern Poland

80%

Bobiec A.

Fragmenta Floristica et Geobotanica

|

1994

|

tom 39

|

nr 2

8

Transport and hydraulically-induced recycling of phosphorus in the North Sea-Baltic Sea transition zone

80%

Kepp R. R., Struve A., Christiansen C., Lund-Hansen L. C., Nielsen M. H., Vang T.

Oceanologia

|

2006

|

tom 48

|

nr 2

Bottom-mounted acoustic Doppler current profiler measurements indicate that the net transport of water (844 m3 s−1) in the Little Belt makes up only 6% of the total transport between the Baltic Sea and the North Sea. This is a smaller percentage than the 9% commonly found in the literature. Owing to barotropic and tidal currents the gross transport is 5 times larger. The net transport is directed towards the North Sea mainly in the top 32 m of the water column but towards the Baltic Sea it occurs in the lower 5 m of the water column. The resulting transport of phosphorus is strongly affected by vertical mixing in an area of hydraulic control in the narrow part of the Little Belt. Comparisons of phosphorus profiles in stratified waters and in the mixing area indicate a yearly entrainment of 15 tonnes P from the bottom water to the surface layer. This vertical transport of P forms part of an internal loop in the general transport between the Baltic Sea and the North Sea. Compared to the transport observed 15–16 years ago, the present net phosphorus transport of 163 tonnes yr−1 from the Baltic Sea through the Little Belt is substantially lower.

9

Estuaries - types, role and impact on human life

71%

Paturej E.

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

|

2008

|

tom 12

Estuaries are transition zones between the land and the sea which form aquatic ecosystems, often referred to as marginal filters. Numerous classifications of estuaries are based on such criteria as: geomorphological structure, the character of water circulation and stratification, the ratio between freshwater and marine water and the type of energy flow. However, not all estuaries fall into one of the above categories. Some of them represent an intermediate type, while the type of others may change depending on the season and related changes in water inflow rate. Fisheries, including bi-valve mollusks, depend on the high productivity of estuarine areas, which can be also used as ports or sites of recreation and industrial activities. Estuaries play a fundamental role in maintaining an ecological balance in the biosphere.

Ograniczanie wyników

The role of ecotones in man-disturbed landscape: boundaries between mixed forest and adjacent man-made ecosystems in the Kampinos National Park, Poland

Crustal structure of the continent-ocean transition zone along two deep seismic transects in north-western Spitsbergen

Location of the transition zone of the Barn Owl subspecies Tyto alba alba and Tyto alba guttata [Strigiformes: Tytonidae]

Altitudinal variation in the diet of sika deer on the Izu Peninsula: patterns in the transitional zone of geographic variation along the Japanese archipelago

Dynamics of sandy desertification and detection of sandy land-steppe boundary: vegetation and soil properties

Distribution of phytoplankton along the thermohaline gradient in the North-Eastern Adriatic channel; winter aspect

The mosaic diversity of ground vegetation along the transect through the transition zone from the pure coniferous to the mixed coniferous site in the Bialowieza Primeval Forest in North-Eastern Poland

Transport and hydraulically-induced recycling of phosphorus in the North Sea-Baltic Sea transition zone

Estuaries - types, role and impact on human life