Population Size and Age Structure of Metamorphic and Pedomorphic Forms ofOmmatotriton ophryticus(Berthold, 1846) in the Northwestern Black Sea Region of Turkey

2013 ◽  
Vol 47 (2) ◽  
pp. 270-276 ◽  
Author(s):  
Eyup Başkale ◽  
Elif Yildirim ◽  
I. Ethem Çevik ◽  
Uğur Kaya
Keyword(s):  
Population Size ◽  
Black Sea ◽  
Age Structure ◽  
Black Sea Region ◽  
Size And Age Structure

Response of Daphnia population size and age structure to predation

1975 ◽  
Vol 19 (4) ◽  
pp. 2898-2905
Author(s):  
Nelson G. Hairston ◽  
Robert A. Pastorok
Keyword(s):  
Population Size ◽  
Age Structure ◽  
Daphnia Population ◽  
Size And Age Structure

scholarly journals Changes in the Ecological Footprint of Rural Populations in the Taihang Mountains, China

2018 ◽  
Vol 10 (10) ◽  
pp. 3741 ◽  
Author(s):  
Xingyuan Xiao ◽  
Minyue Hu ◽  
Minghong Tan ◽  
Xiubin Li ◽  
Wei Li
Keyword(s):  
Population Size ◽  
Age Structure ◽  
Rural Areas ◽  
Ecological Footprint ◽  
Environmental Changes ◽  
Northern China ◽  
Practical Significance ◽  
Urban Migration ◽  
Mountainous Areas ◽  
Size And Age Structure

Due to massive rural–urban migration, population size and age structure are subject to significant changes in the mountainous areas of China. This can influence the ecological pressure of the mountainous areas correspondingly. In particular, large numbers of young laborers migrate from rural areas, which may greatly decrease the intensity of local human activities. However, it is still unclear how population changes (size and age structure) affect environmental changes and how to measure these changes. We analyzed changes in the ecological footprint (EF) in the Taihang Mountain region in northern China using field survey data. From 2000 to 2016, the population size in the study area decreased by 9.7%, while the EF declined by 32.1%. The EF per capita (EF_per) decreased more rapidly with decreasing elevation, which indicated that at lower elevations, households were less dependent on local resources. For households with more elderly people, the EF_per was considerably lower than for other households in 2000. However, in 2016, this was not the case, and the households with a share of the working-age population between 50–75% had the lowest EF_per. Our study is of great practical significance for reasonably guiding population migration and rural sustainable development.

Littoral invertebrates in waders’ nutrition at migratory stopover sites in the Azov and Black Sea region

2014 ◽  
Vol 25 (1-2) ◽  
pp. 69-82 ◽  
Author(s):  
L. P. Kharchenko ◽  
I. A. Lykova
Keyword(s):  
Fatty Acids ◽  
Black Sea ◽  
Biochemical Markers ◽  
Artemia Salina ◽  
Total Lipids ◽  
Long Distance ◽  
Black Sea Region ◽  
Stopover Sites ◽  
Littoral Invertebrates ◽  
Migratory Stopover

Seasonal migration for birds – distant migrants are the most energy intensive. Fat reserves accumulated in the bird’s body before migration and during migratory stopovers determine success of the long-distance flight. Lipids play a vital role both as a source of energy and as structural components of cell membranes. For most migrants to the speed and quality processes fat accumulation affects the feed ration in the field of migration stops. Fodder saturation with essential polyunsaturated fatty acids (PUFAs) is of great importance. Being paramount for physiological processes, these acids cannot be synthesized in the bird’s body. The proposed article is dedicated to the study of waders’ trophic relationships with their prey items, and the use of PUFAs as biochemical markers. This approach is based on the specificity of the fatty acids contained in the lipids of invertebrate to be used as food bird species studied. Significant amount NPZHK waders obtained from forage that can be considered PUFAs as biochemical markers to determine the range and diversity of food producing birds PUFAs ways, and also to study the food chain in ecosystems. A fatty acid spectrum (FAS) of the lipids common for nine littoral invertebrate species (Gammarus aequicauda, Idotea balthica, Artemia salina, Nerеis sp., Nerеis zonata, Theodoxces astrachanicus, Hydrobia acuta, Chironomus salinarius, Chironomus plumosus), which constitute the main component of waders’ diet at the migratory stopover sites in the Azov and Black Sea region, has been studied. Found that the largest amount of total lipids contained in Nereis zonata (4,6 %) and Artemia salina (4,4 %), the lowest amount of total lipids was observed in Chironomus (1,5–1,8 %), which implies that polychaete worms and Artemia salina, as a source of fat, are the most productive for waders. Our research has found that mollusks, polychaete worms, and Artemia salina are the most effective waders’ fodder in the PUFAs content. Mollusks contain the largest amount of PUFAs, their spectrum is ω3 and ω6 PUFAs, especially arаchidonic acid C20:4. Polychate worms are also characterized by a high PUFAs level; they serve for birds as a source of linolenic and linoleic acid groups. Artemia salina contains a large amount of eicosapentaenoic С20:5ω3 and docosahexaenoic С22:6ω3 acids, which getting to an organism of birds, participating in the formation of cell membranes, act as thermal stabilizer lipid bilayers, enhance stamina during long-distance flight. A high abundance of Artemia salina in the feeding areas permit tundra waders to use them as a prey item, which can fulfill the bird’s body with a required amount of fatty acids in a short time. We have established an influence of some environmental factors, as water temperature and salinity, on the lipids FAS of littoral invertebrates. Spectrum analysis of polyene fatty acids in the lipids closely related species of invertebrates living in different salinity water showed that the content of PUFAs in the lipid depend on their food spectrum, and the environmental conditions. Therefore, anthropogenic pressure and changes of water hydrological regime may affect PUFAs content in the lipids of littoral invertebrates. In its turn, this factor may change alimentary behavior and migratory strategy of the birds, which use migratory stopover sites in the region in question. Shallow waters of the Azov-Black Sea region are characterized by different climatic characteristics and a large reserve of phytoplankton. This explains the mass character species studied of invertebrates to feeding areas and their use as basic prey items, many species of waders.

Current Status of Anserinae Wintering in Azov-Black Sea Region of Ukraine

2019 ◽  
Vol 53 (4) ◽  
pp. 297-312
Author(s):  
Yu. O. Andryushchenko ◽  
V. S. Gavrilenko ◽  
V. A. Kostiushyn ◽  
V. N. Kucherenko ◽  
A. S. Mezinov ◽  
...  
Keyword(s):  
Black Sea ◽  
Current Status ◽  
Anser Anser ◽  
Scientific Publications ◽  
Climate Conditions ◽  
Black Sea Region ◽  
Chen Caerulescens ◽  
Branta Bernicla ◽  
The North ◽  
Different Seasons

Abstract In the article is analyzed own field data of the authors and scientific publications on the wintering of Anserinae in the Azov-Black Sea region of Ukraine in 1900–2017, but the main data was obtained in frame of international mid-winter counts (IWC) in 2005–2017. It was found that 9 species of Anserinae occur in this region during the different seasons of the year: Anser anser — nesting, wintering and migrating; Rufibrenta ruficollis, A. albifrons, A. erythropus, A. fabalis — migrating and wintering; Branta canadensis, Branta leucopsis, Branta bernicla, Chen caerulescens — vagrant or birds which flew away from captivity (zoo etc.). Eulabeia indica — is possible vagrant species. The most numerous wintering species is A. albifrons, common — Rufibrenta ruficollis, not numerous — Anser anser, the other species are not met annually and registered in a very small number. There was almost tenfold drop in number of wintering geese in the Azov-Black Sea region of Ukraine during the period of counts. The main reasons of such reducing of geese amount are the followwing: weather and climate conditions, changes in the forage acessibility, hunting and poaching pressure, poisoning as a result of deratization of agricultural lands, and from 2014 — the militarization of the Syvash area and stop of water supplying of Crimea through the North Crimean channell. It is likely that the factors mentioned above led to relocating of wintering areas of Anserinae, and resulted in decreasing of their amount in this region.

Sign in / Sign up

Export Citation Format

Share Document