Demographic and genetic evidence of the long-term recovery of (Daphnia galeata mendotae) (Crustacea: Daphniidae) in Sudbury lakes following additions of base: the role of metal toxicity

1996 ◽  
Vol 53 (6) ◽  
pp. 1328-1344 ◽  
Author(s):  
N D Yan ◽  
P G Welsh ◽  
H Lin ◽  
D J Taylor ◽  
J -M Filion
1993 ◽  
Vol 50 (10) ◽  
pp. 2137-2146 ◽  
Author(s):  
Derek J. Taylor ◽  
Paul D. N. Hebert

Seasonal, within-lake, and among-lake variation in helmet size and shape has been reported for Daphnia galeata mendotae. The genetic component of this variation was assessed by an allozyme and morphological reanalysis of nine previously studied sites. Genetic associations with morphological variation were found, but all were attributed to D. galeata mendotae × Daphnia rosea hybridization or to taxonomic confusion with D. rosea. The existence of hybrids accounted for spatial polymorphism both within and among lakes. In addition, hybrids contributed to seasonal variation as they increased in abundance from summer to winter. Nevertheless, cyclomorphosis in D. galeata mendotae s.s was real and due largely to phenotypic plasticity. Local hybridization between D. galeata mendotae and D. rosea was widespread from the midwestern states to Vermont. The distributions and habitat associations of D. galeata mendotae and D. rosea indicated that ecological segregation at the lake level acts as an important reproductive isolating mechanism. Reinterpretation of previous studies, however, suggests that disturbance followed by one or a few hybridization events often leads to hybrid domination of a lake.


2013 ◽  
Author(s):  
Francesca Menegazzo ◽  
Melissa Rosa Rizzotto ◽  
Martina Bua ◽  
Luisa Pinello ◽  
Elisabetta Tono ◽  
...  

2014 ◽  
pp. 30-52 ◽  
Author(s):  
L. Grigoryev ◽  
E. Buryak ◽  
A. Golyashev

The Ukrainian socio-economic crisis has been developing for years and resulted in the open socio-political turmoil and armed conflict. The Ukrainian population didn’t meet objectives of the post-Soviet transformation, and people were disillusioned for years, losing trust in the state and the Future. The role of workers’ remittances in the Ukrainian economy is underestimated, since the personal consumption and stability depend strongly on them. Social inequality, oligarchic control of key national assets contributed to instability as well as regional disparity, aggravated by identity differences. Economic growth is slow due to a long-term underinvestment, and prospects of improvement are dependent on some difficult institutional reforms, macro stability, open external markets and the elites’ consensus. Recovering after socio-economic and political crisis will need not merely time, but also governance quality improvement, institutions reform, the investment climate revival - that can be attributed as the second transformation in Ukraine.


2006 ◽  
pp. 4-19 ◽  
Author(s):  
L. Abalkin

The article covers unified issues of the long-term strategy development, the role of science as well as democracy development in present-day Russia. The problems of budget proficit, the Stabilization Fund issues, implementation of the adopted national projects, an increasing role of regions in strengthening the integrity and prosperity of the country are analyzed. The author reveals that the protection of businessmen and citizens from the all-embracing power of bureaucrats is the crucial condition of democratization of the society. Global trends of the world development and expert functions of the Russian science are presented as well.


2013 ◽  
pp. 143-155
Author(s):  
A. Klepach ◽  
G. Kuranov

The role of the prominent Soviet economist, academician A. Anchishkin (1933—1987), whose 80th birth anniversary we celebrate this year, in the development of ideas and formation of economic forecasting in the country at the time when the directive planning acted as a leading tool of economic management is explored in the article. Besides, Anchishkin’s special role is noted in developing a comprehensive program of scientific and technical progress, an information basis for working out long-term forecasts of the country’s development, moreover, his contribution to the creation of long-term forecasting methodology and improvement of the statistical basis for economic analysis and economic planning. The authors show that social and economic forecasting in the period after 1991, which has undertaken a number of functions of economic planning, has largely relied on further development of Anchishkin’s ideas, at the same time responding to new challenges for the Russian economy development during its entry into the world economic system.


1996 ◽  
Vol 35 (4I) ◽  
pp. 385-398 ◽  
Author(s):  
John C. Caldwell

The significance of the Asian fertility transition can hardly be overestimated. The relatively sanguine view of population growth expressed at the 1994 International Conference for Population and Development (ICPD) in Cairo was possible only because of the demographic events in Asia over the last 30 years. In 1965 Asian women were still bearing about six children. Even at current rates, today’s young women will give birth to half as many. This measure, namely the average number of live births over a reproductive lifetime, is called the total fertility rate. It has to be above 2— considerably above if mortality is still high—to achieve long-term population replacement. By 1995 East Asia, taken as a whole, exhibited a total fertility rate of 1.9. Elsewhere, Singapore was below long-term replacement, Thailand had just achieved it, and Sri Lanka was only a little above. The role of Asia in the global fertility transition is shown by estimates I made a few years ago for a World Bank Planning Meeting covering the first quarter of a century of the Asian transition [Caldwell (1993), p. 300]. Between 1965 and 1988 the world’s annual birth rate fell by 22 percent. In 1988 there would have been 40 million more births if there had been no decline from 1965 fertility levels. Of that total decline in the world’s births, almost 80 percent had been contributed by Asia, compared with only 10 percent by Latin America, nothing by Africa, and, unexpectedly, 10 percent by the high-income countries of the West. Indeed, 60 percent of the decline was produced by two countries, China and India, even though they constitute only 38 percent of the world’s population. They accounted, between them, for over threequarters of Asia’s fall in births.


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