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Ecological conflicts in Poland 总被引：1，自引：0，他引：1
Transformation of the political system, observed in Poland for 10 years in connection with economic restructuring and basic
socio-economic reforms to harmonise with European Union structures, is also evident in terms of environmental management.
Pollution has been reduced in many ways but the rise in living standards, linked with the rapid growth of cars and other forms
of consumption, has had a negative effect and environmental conditions have deteriorated in the central areas of large cities.
The growth of waste water and refuse is a considerable problem. More areas are now officially protected and the three levels
of local government established at the beginning of January 1999 (voivodeship, district and community) all have certain defined
environmental protection responsibilities which are cumulatively greater than before. Meanwhile there is a greater awareness
in society of environmental issues, although it does not yet lead to a high level of participation in protection work. However,
there are strongly-expressed opinions on the ecological acceptability of certain economic developments and conflicts are frequently
arising within communities and local governments and also between investors on the one side and ecological organisations and
environmental protection institutions on the other. Most controversial are new roads, power stations (like the Zarnowiec nuclear
project) and reservoirs like the one on the Dunajec river at Czorsztyn. Local communities frequently resist plans for waste
dumps, incinerating plants and other developments which are seen as injurious to health or the quality of life. The planned
reprivatisation of the state-owned forests is also criticised by foresters and ecological movements. Conflicts are likely
to grow as economic development accelerates but better information and greater public understanding of the need for sustainability
should make for consensus.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
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Joshua Kurek Les C. Cwynar Thomas A. Ager Mark B. Abbott Mary E. Edwards 《Quaternary Science Reviews》2009,28(9-10):799-811
Fossil Chironomidae assemblages (with a few Chaoboridae and Ceratopogonidae) from Zagoskin and Burial Lakes in western Alaska provide quantitative reconstructions of mean July air temperatures for periods of the late-middle Wisconsin (～39,000–34,000 cal yr B.P.) to the present. Inferred temperatures are compared with previously analyzed pollen data from each site summarized here by indirect ordination. Paleotemperature trends reveal substantial differences in the timing of climatic warming following the late Wisconsin at each site, although chronological uncertainty exists. Zagoskin Lake shows early warming beginning at about 21,000 cal yr B.P., whereas warming at Burial Lake begins ～4000 years later. Summer climates during the last glacial maximum (LGM) were on average ～3.5 °C below the modern temperatures at each site. Major shifts in vegetation occurred from ～19,000 to 10,000 cal yr B.P. at Zagoskin Lake and from ～17,000 to 10,000 cal yr B.P. at Burial Lake. Vegetation shifts followed climatic warming, when temperatures neared modern values. Both sites provide evidence of an early postglacial thermal maximum at ～12,300 cal yr B.P. These chironomid records, combined with other insect-based climatic reconstructions from Beringia, indicate that during the LGM: (1) greater continentality likely influenced regions adjacent to the Bering Land Bridge and (2) summer climates were, at times, not dominated by severe cold. 相似文献
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Despite substantial rural-urban migration, 38.1 percent of the population of Poland still live in the countryside and the
total numbers are only 0.9mln fewer than in 1946. At present the rural population is increasing and the rate of natural increase
(though falling) is higher than in the towns though the productive age group is smaller. However, these human resources are
not being properly used and the results can be seen in terms of economic inefficiency, low living standards and a high level
of state support. Loss of jobs in factories and state farms results in welfare payments by the state and considerable 'hidden
unemployment' on small family farms where profitability is constrained by inefficient use of labour. Poverty among the rural
population is evident through a collapse of house building and considerable domestic overcrowding. However, conditions vary
considerably across the country and this must be reflected in the economic and social policies drawn up for the new administrative
regions introduced in 1999.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
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Summary Smoothing time series of measurements is usually employed to remove high frequency noise when it is necessary to interpolate
them for dates where no measurements are available, and also in an attempt to free the series from their short-term instability
in order to provide an improved representation of the measured quantity.
Two methods are currently used in connection with the Earth's rotation studies: Vondrak's algorithm and a moving average with
a Gaussian weighting function [Gaussian smoothing). This study describes their behaviour in terms of frequency filtering and
of the response in the time domain. Examples of their application to the Earth Rotation Parameters are given. 相似文献
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Size attributes of the cladoceran taxon Bosmina are known to vary in response to the intensity and dominant type of predation. Using a paleolimnological approach, we tested the hypothesis that Bosmina size structure differs between fishless lakes and those with presumed populations of planktivorous fish. We measured sedimentary remains of Bosmina longirostris and assessed assemblage structure of the gape-limited invertebrate predator Chaoborus within the surface sediments of 29 lakes in remote, northwestern Ontario, Canada. Mean B. longirostris mucro, antennule, and carapace lengths did not differ significantly between lake predation categories. However, within fishless lakes, a significant (r = 0.68, P = 0.01) positive correlation was apparent between B. longirostris mucro length and Chaoborus americanus percent abundance. We thus suggest that B. longirostris mucro length may be sensitive to C. americanus predation, however further information on the interactions with predators is needed. 相似文献
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Journal of Paleolimnology - Human activities in the headwaters of the Carleton River Watershed (southwest Nova Scotia, Canada) are suspected to have led to nutrient enrichment of freshwaters,... 相似文献
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We examined the relationship between three key environmental variables (water depth, loss-on-ignition, and bottom-water temperature)
and fossil chironomid distributions sampled from within-lake gradients in three small, moderately deep (18–35 m), maar lakes
on St Michael Island, western Alaska. Site-specific (one lake, 29 samples) and local (three lakes, 87 samples) inference models
for reconstructing water depth were developed using partial least squares regression and calibration. These models and a previously
published regional model (136 lakes, one central-lake sample from each) are used to infer water depths from 78 fossil samples
spanning the last ~30,000 14C years B.P. at Zagoskin Lake. Although the site-specific [r
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boot = 0.90, root mean square error of prediction (RMSEP) = 1.76] and local (r
boot2 = 0.68, RMSEP = 4.36) inference models have better performance statistics than the regional model, few clear trends among
all three models exist in the lake-level reconstruction. We propose that multiple, within-lake sampling of gradients can be
used to improve the performance statistics of water-depth transfer functions and ultimately reconstruct paleohydrology in
regions known to exhibit large fluctuations in moisture balance through time given that: (1) adequate analogs are established
and (2) taphonomic processes important to benthic invertebrate remains are more fully understood. 相似文献
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