scholarly journals Specific composition, numbers and biotopical distribution of snakes (Serpentes) on the southern slope of the Navagir mountain ridge (Abrau Peninsula) and some problems of its preservation

2021 ◽  
Vol 21 (3/4) ◽  
pp. 144-150
Author(s):  
A. Yu. Tsellarius ◽  

Seven species of snakes were revealed in 1997–1998, six of which (Natrix tessellata, N. natrix, Zamenis longissimus, Hierophis caspius, Platyceps najadum, and Elaphe sauromatus) were in the lower part of the slope, in the area of mediterranean vegetation. In 2001– 2003, the first three species were revealed only, and their numbers significantly decreased, reaching a maximum in the middle part of the slope, in the zone of transition from mediterranean vegetation to broad-leaved forests. In 1999–2000, the recreational load on the coastal area sharply rose, which probably was the cause for the species composition reduction and changes of the spatial distribution in snakes.

2015 ◽  
Vol 48 (3) ◽  
pp. 786-796 ◽  
Author(s):  
Maheswar Nayak ◽  
P. C. Pradhan ◽  
G. S. Lodha

Element-specific structural analysis at the buried interface of a low electron density contrast system is important in many applied fields. The analysis of nanoscaled Si/B4C buried interfaces is demonstrated using resonant X-ray reflectivity. This technique combines information about spatial modulations of charges provided by scattering, which is further enhanced near the resonance, with the sensitivity to electronic structure provided by spectroscopy. Si/B4C thin-film structures are studied by varying the position of B4C in Si layers. Measured values of near-edge optical properties are correlated with the resonant reflectivity profile to quantify the element-specific composition. It is observed that, although Si/B4C forms a smooth interface, there are chemical changes in the sputtered B4C layer. Nondestructive quantification of the chemical changes and the spatial distribution of the constituents is reported.


2019 ◽  
Vol 131 ◽  
pp. 01044
Author(s):  
Rong-rong Yang ◽  
Guang-chao Cao ◽  
Sheng-kui Cao ◽  
Yao Lan ◽  
Zhuo Zhang ◽  
...  

Based on the NPP products of MODIS data, the spatial and temporal distribution characteristics of grassland NPP and its response to climatic factors in the vegetation growing season of the main river valleys in the southern slope of Qilian Mountains from 2000 to 2016 were carried out by correlation analysis and spatial interpolation. The research further provides a scientific basis for the quality evaluation of grassland ecosystems on the southern slope of Qilian Mountain and the rational use of grassland resources along the river. The results show that: (1) With the increasing distance of buffers on both sides of the river, the NPP of grassland in each year shows the characteristics of “single-peak” distribution, which is increased first and then decreased; (2) the NPP of grassland in the main river valley of the southern slope of Qilian Mountain The spatial distribution characteristics show a trend of increasing from northwest to southeast. (3) The spatial distribution of NPP and air temperature in the main river valleys of the southern slope of Qilian Mountains is gradually increasing from northwest to southeast, but the spatial distribution correlation coefficient of NPP and precipitation in the river valley grassland of vegetation growing season basically shows a trendof decreasing from northwest to southeast.


Author(s):  
Edgar Lanz ◽  
Manuel O. Nevárez Martínez ◽  
Juana López Martínez ◽  
Juan A. Dworak

1991 ◽  
Vol 7 (2) ◽  
pp. 221-232 ◽  
Author(s):  
George Idodo-Umeh ◽  
Reginald Victor

ABSTRACTSome aspects of the ecology of bagrid catfishes in River Ase, southern Nigeria were studied for a period of two years. Nine species of Bagridae were recorded and these accounted for 15.0% of the number and 24.4% of the weight of all fish captured. Chrysichthys nigrodigitatus and Chrysichthys auratus longifilis were the principal species. C. nigrodigitatus was a rainy season species, while C. auratus longifilis was abundant in both dry and rainy seasons. Both species showed a major peak in catches between 0600 and 0900 h. C. nigrodigitatus exhibited a minor peak in catches between 1500 and 2100h, while C. auratus longifilis showed a minor peak between 1500 and 1800h. The spatial distribution of C. nigrodigitatus and C. auratus longifilis populations was heterogeneous. Bagrid fishes were an important component in the fish yield of the study river and its species composition has been compared with those of other Nigerian waters. The distribution and abundance of C. nigrodigitatus and C. auratus longifilis are discussed in detail.


1956 ◽  
Vol 7 (3) ◽  
pp. 317 ◽  
Author(s):  
R Endean ◽  
W Stephenson ◽  
R Kenny

The species composition and general ecology of intertidal organisms present at Heron Island, a coral cay in the Capricorn Group, are recorded in this paper. It was found that the general zonation picture on this Great Barrier Reef island differed markedly from that found previously at localities on the Queensland mainland (Endean, Kenny, and Stephenson 1956). In particular the mainland upper barnacle (Chthamalus) zone was not represented at Heron I., and the species forming the mainland lower barnacle zone (Tetraclita squamosa (Bruguiere) ) was replaced by a different species (Tetraclita vitiata Darwin). Also the characteristic algal zone of mainland localities was replaced by a lithothamnion-zoanthid-coral zone. In order to investigate the possibility of a gradual transition from the mainland type zonation to that found on the Great Barrier Reef, as exemplified by Heron I. zonation, the species composition and general ecology of intertidal organisms inhabiting a series of continental islands lying off the Queensland coast between lat. 16� and 22� S. were investigated. The fauna of these islands was found to be closely allied to that of the mainland. There was, however, an intrusion of corals and zoanthids on the more exposed of the islands visited which lie between lat. 20� and 22�S., and also on the more northerly of the islands visited. The biogeographical implications of these findings are discussed, and it is noted that the results of the present investigation support the contention of Whitley (1932) that a longitudinal division of the Queensland marine fauna into "Solanderian" and "Banksian" elements is warranted. Accounts are also given of the major environmental factors that might affect specific composition and zonation patterns at the localities investigated. Analyses of these have given much information on the general ecology and distribution of many Queensland intertidal species. Thls information is discussed. Of particular interest was the finding that the Peronian barnacle Tetraclita rosea (Krauss) has extended its range,to the north of the biogeographical boundary situated near lat. 25� S. by colonizing the more exposed of the continental islands.


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