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1

Notes on the effects of human induced stressors in parts of the Niger Delta, Nigeria

100%
Nwankwo D. I.
Polish Ecological Studies
|
1996
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tom 22
|
nr 1-2
2

Can naturalness indicator values reveal habitat degradation? A test of four methodological approaches

72%
Erdos L., Batori Z., Penksza K., Denes A., Kevey B., Kevey D., Magnes M., Sengl P., Tolgyesi C.
Polish Journal of Ecology
|
2017
|
tom 65
|
nr 1
Assessing habitat naturalness belongs to the most current issues in conservation biology. It has been recognized that plants are able to indicate the naturalness of their habitat. Thus, species may be given relative naturalness indicator values (i.e. scores on an ordinal scale), reflecting their different tolerances against habitat degradation. In the present study, our first goal was to test whether relative naturalness indicator values are able to reveal known differences in naturalness levels. Our second purpose was to compare four different methodological approaches in order to identify which is the most reliable when analyzing habitat naturalness. We compared near-natural and degraded plots on the bases of (1) unweighted plot means, (2) plot medians, (3) unweighted naturalness indicator value populations, and (4) frequency-weighted naturalness indicator value populations. We found that relative naturalness indicator values performed well in differentiating among near-natural and degraded vegetation. Unweighted mean indicator values were the most reliable, but frequency-weighted indicator value populations were nearly as efficient as unweighted means. We conclude that relative naturalness indicator values provide a simple but reliable tool for estimating habitat deterioration.
3

Effect of vegetation and soil conditions on burrow structure and site selection of rare desert rodent – Iranian jerboa (Allactaga firouzi)

58%
Naderi G., Hemami M. R., Mohammadi S., Riazi B., Karami M., Kaboli M., Alesheikh A. A.
Polish Journal of Ecology
|
2011
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tom 59
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nr 2
The Iranian jerboa (Allactaga firouzi Womochel, 1978) is one of the rarest rodent species in the world and it has been reported exclusively from a single site in central Iran. Because of its restricted geographical distribution and habitat degradation, it has been classified as Critically Endangered in the IUCN Red List. From April 2007 to February 2009 on a small area (2200 ha) of semi-arid grazed steppe (altitude 2000 m, surface covered by bare soil and/or scarce shrub and grass vegetation) we studied the architecture structure of burrow system and burrow site selection of Iranian jerboa. Three types of burrows including temporary burrows, winter and s ummer burrows were detected in the studied habitat. Habitat characteristics such as the percentage cover of: bare soil, pebble and cobble and desert plant species like Anabasis aphylla, Artemisis siberi, and Peganum harmala, as well as the selected chemical soil parameters (content of calcium sulfate, calcium carbonate) were measured in the burrow sites and compared with similar variables measured at random plots in the non-burrow sites. The principal component analysis successfully distinguished between the burrow sites and the non-burrow areas. The burrow site selection was mainly influenced by percentage cover of bare soil, vegetation type, soil texture and chemistry.
4

Fish and land-inland water ecotones - overview and synthesis

58%
Zalewski M., Schiemer F., Thorpe J.
International Journal of Ecohydrology and Hydrobiology
|
2001
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tom 01
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nr 1-2
The dramatic depletion of diversity and standing crop of freshwater fish has been due mostly to degradation of their habitats and water quality. To halt and reverse this negative trend, a new approach is needed urgently toward sustainability of fish resources. The UNESCO MAB programme on the role of land-water ecotones has opened a new perspective towards solving problems in landscape management and conservation. Land-water ecotones, if restored and managed in a sustainable way, can buffer and filter impacts on aquatic ecosystems due to catchment development, by moderating hydrological processes, improving water quality, and increasing spatial complexity of habitats. This way, fish resources can be safeguarded, restored and sustained. The programme of the 'Fish and Land-Inland Water Ecotones' (FLIWE) team has shown strong links between fish life histories and structures and processes in land-water ecotones. To be able to sustain freshwater fish populations a good understanding is needed of the biological linkages and pathways through land-water ecotones; of biogeochemistry; of modern techniques for habitat inventories; and of methods of habitat evaluation, planning and assessment of socio-economic feedback.
5

Small-mammal assemblages inhabiting Sphagnum peat bogs in various regions of Poland

51%
Ciechanowski M., Cichocki J., Wazna A., Pilacinska B.
Biological Letters
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2012
|
tom 49
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nr 2
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