[Dynamics of colonies of the speckled ground squirrel (Spermophilus suslicus Guld., 1770) on the northern boundary of the habitat].

Results of studies in 1999-2009 of the dynamics of five isolated colonies of the speckled ground squirrel (Spermophilus suslicus) at the northern boundary of the habitat of this species (Zaraiskii area, Moscow oblast) are given. An abrupt decrease in the number of this species in colonies was established, as was a multifold decrease (up to 70-90%) in suitable habitats due to the plowing of meadows and build-up of the area. The fragmentation of the optimum habitat of ground squirrels reached a stage where colonies can no longer exist as a stable autonomous system. The process of their extinction unfolds quickly: the number of animals in some colonies decreased five-six times over the last ten years. To preserve this species, it is necessary to create areas of steppefied meadows with regulated agricultural use.

[Dynamics of rodent community and populations in Kalmyk semideserts under decreasing pasture load and increasing humidity]. / Dinamika soobshchestva i populiatsii gryzunov polupustyn' Kalmykii v usloviiakh snizheniia nagruzki na pastbishcha i uvlazhneniia klimata.

Today, pastural ecosystems of the Kalmyk Republic demonstrate progressive regrowth dynamics, which is explained by a sharp decrease in grazing load and the onset of a new humidification cycle in the Caspian Lowland. By the mid-1990s, the sparse and poor desert vegetation with a significant proportion of ephemerals, characteristic of these ecosystems in the 1980s, had been substituted by highly productive tall-grass communities typical of steppes. Under such conditions, corresponding changes in the distribution and abundance of rodents could be expected. These parameters were assessed in different types of habitats in Chernye Zemli (the Kalmyk Black Lands) from 1980 to 1983 and from 1993 to 1997. Rodents were captured in live traps distributed over permanent test plots and in crush traps arranged in lines. The results showed that the population of midday gerbils did not change significantly during this period, although their favorite open habitats considerably decreased in area. The abundance and range of tamarisk gerbils noticeably increased, whereas those of little sousliks continued to decrease, contrary to our expectations. Thus, a rapid progressive succession in plant communities did not cause the corresponding change (of similar rate and extent) in the structure of rodent community. The difference between the observed and expected results provides evidence that rodent populations are somewhat "inert" in their response to changes in environmental conditions, and their development is relatively independent of these changes, but is contingent upon the state of populations in the past (i.e., the history of colonies).

[Relationship between zoonotic cutaneous leishmaniasis morbidity in the Murgab oasis and hydrometeorological factors]. / Analiz sviazei zabolevaemosti zoonoznym kozhnym leishmaniozom v Murgabskom oazise s gidrometeorologicheskimi faktorami.

The relationships of changes in the incidence of zoonotic cutaneous leishmaniasis (ZCL) in the Mary velayat, Turkmenistan, to those in hydrometeroelogical factors in 1951 to 1993 were first analyzed and the regularities found were evaluated. There is an inverse relationship of the incidence to the temperatures of the preceding winter. The long persistence of sun shining seems to have a negative impact on the foci of ZCL. There is an insignificant correlation of humidity, precipitation, and winds. In the years marked by high waters in the valley foci, increased soil moisture content causes a reduction in their epidemic activity.

[The multiyear changes in the epidemic activity of the foci of zoonotic cutaneous leishmaniasis at the Murgab oasis. I. An analysis of the relations of morbidity to heliogeophysical factors]. / Mnogoletnie izmeneniia épidemicheskoi aktivnosti ochagov zoonoznogo kozhnogo leishmanioza v Murgabskom oazise. Soobshchenie I. Analiz sviazei zabolevaemosti s geliogeofizicheskimi faktorami.

Attempts were made to analyse the relationships of changes in the pattern of zoonotic cutaneous leishmaniasis (ZCL) morbidity by the 1951-1993 statistics of the Turkmenistan Ministry of Health by the areas of Maryiskii velaiat with heliogeophysical factors. For quantitative characterization of solar activity changes, various indices were used; among them there was the Wolf number, radio radiation flux at a wavelength of 10.7 cm. and the geomagnetic Aa-index. In some many-year observations, vague cyclic variations were detected on a personal computer by spectral and periodogram analyses proved to be effective in other diseases. Correlation and cross-correlation analyses were used to evaluate the possible relationships between the morbidity rates and the changes in heliogeophysical factors. The study has revealed that the epidemic activity of ZCL foci is characterized by cyclicity with variations of about 2.4, 3.6, 6.9, and 11.2 years. The changes in ZCL morbidity in the areas, including the natural ZCL foci of Murgab delta landscapes, slightly differ from those in the areas with valley foci in the south part of the velayat in the duration and expression of cycles. At the same time sun-caused 11-year cycles are observed in all groups of the areas, though they are slightly more pronounced in the north than in the south. The greatest epidemic outbreaks (1956-1957, 1965, 1977, and 1986-1988) occurred in various areas of the Murgab oasis on an average of 1-3 years after the minimum of 11-year solar cycles. Noteworthy, they are greatly marked in odd solar activity cycles (the 1957 and 1977 outbreaks) in many areas. Among the parameters chosen, the radio flux of solar radiation at a wavelenght of 10.7 cm and the Wolf number (the correlation coefficients are as high as 0.30-0.50 at P = 0.95) are closely related with ZCL morbidity changes when the plot is shifted. At the same time the values of the geomagnetic Aa-index are unlikely to greatly affect changes in the epidemiological situation. The regularities revealed are of particular significance for long-term prediction of the greatest rises of ZCL morbidity rates. Taking into account the estimated solar activity changes within the next years, one may expect activation of natural ZCL foci and, in case of untimely use of prophylactic measures, the following rise in the population's morbidity in 1998-1999.