Архив метки: ecological condition

ASSESSING THE IMPACT OF AVIARY HOUSING OF ANIMALS ON THE ECOLOGICAL CONDITION OF SOILS

Arid Ecosystems

UDC 631.4; 574.4

Gobarova A.A., Kazeev K.Sh., Zhadobin A.V.,  Fedorenko A.N., Kolesnikov S.I. ASSESSING THE IMPACT OF AVIARY HOUSING OF ANIMALS ON THE ECOLOGICAL CONDITION OF SOILS // Arid Ecosystems. 2023. Vol. 29. № 2 (95). P. 109-117. | PDF

The activities of animals have a significant impact on the area of their habitat. The objects under our study are located in the dry steppes zone, the climate of which limits the development of vegetation and contributes to changes in soil characteristics, which, combined with the impact of animals, increases its effect. The aim of our work was to assess the impact of animals on the ecological condition of the soils in the enclosures of the “Wildlife Steppe” Association (orig. “Zhivaya Priroda Stepi”).

During our study, the main indicators of the ecological state of soil in the enclosures with animals, located in the arid area of Rostov Region, were determined. We studied enclosures of different sizes, with common ostriches (Struthio camelus), emus (Dromaius novaehollandiae), goats (Capra sp.), Przewalski’s horses (Equus ferus przevalskii) and saiga antelopes (Saiga tatarica), and the grazing areas of horses (Equus caballus), Bactrian camels (Camelus bactrianus), wild water buffalos (Bubalus arnee), wild yaks (Bos mutus) and guanacos (Lama ganicoe). Level of soil degradation differed from area to area. Soil moisture, temperature, density and texture were determined to assess the physical condition, pH, gross soil chemistry, humus content and biological activity; then the plots were ranked according to the degree of pasture degradation.

The enclosure of common ostriches had the maximum degradation of 10 degrees, characterized by severe vegetation depression and soil battering. The soil density in their enclosure was also the highest and reached 1.49 g/cm3, while the structure was the lowest and reached only 37%. These parameters had a strong negative correlation with hoof and foot pressure on the soil (-0.9). Moisture levels never exceeded 11% in the study areas, although soil enzymatic activity was more influenced by animal excreta than by hydrothermal conditions. In the enclosures with ungulates, goats in particular, catalase and urease activity was always higher than in other plots. There was also a high humus content (10.3%), uncharacteristic for chestnut soils and confirmed by the influence of animals’ activity.

According to the results of our study, the lowest values of structure, humus and biological activity, as well as increased density of soil compaction, were in the enclosure with common ostriches. The findings explain the reduced growth and development of vegetation in the area where the animals were kept in crowded conditions.

Keywords: pasture digression, ecological condition, enzymatic activity, bioindication, content of organic matter, physical properties.

Financing. The research was supported financially by the leading scientific school of Russia “Assessment and Forecast of Soil Conditions under Various Anthropogenic Influences and Climate Change” (NSH-449.2022.5).

DOI: 10.24412/1993-3916-2023-2-109-117

EDN: WRCBNN

HYDROECOLOGICAL CONDITION OF THE AGRAKHAN BAY AND POSSIBILITIES FOR ITS IMPROVEMENT

Arid Ecosystems

UDC 556.545, 574.5, 639.2/3

Magritsky D.V., Goncharov A.V., Moreido V.M., Samokhin M.A., Abdusamadov A.S., Kuptsov S.V., Dzhamirzoev G.S., Erina O.N., Sokolov D.I., Arkhipkin V.S., Tereshina M.A., Surkov V.V., Semenova A.A. Hydroecological Condition of the Agrakhan Bay and Possibilities for Its Improvement // Arid Ecosystems. 2022. Vol. 28. № 4 (93). P. 163-178. | PDF

In the XX century, as a result of a combination of natural and anthropogenic factors, there was a significant transformation of the Agrakhan Bay on the eastern coast of the Terek Delta. The comprehensive studies carried out in 2018-2020 made it possible to identify the main causes of this degradation, characterize the current state of the reservoir and scientifically substantiate recommendations for its improvement. It is shown that as a result of shallowing and reduction of the area of the water mirror, the bay has lost its former significance as a spawning and growing reservoir that provides the Western Caspian region with young valuable commercial fish species. Catches by 2018 fell by 10 times compared to the beginning of the XX century; sturgeon, which used to be famous for the Agrakhan Bay, practically disappeared. Especially unfavorable is the state of the northern part of the bay, which has turned into a group of shallow reservoirs, little connected with each other and with the sea. And the situation continues to deteriorate every year.

The study of hydrological-morphological, hydrobiological, fishery, hydrochemical parameters showed that there is hope for improving the condition of wetlands on the site of the former bay. A detailed analysis of the water balance using multivariate limnological calculations showed that there is sufficient water for flooding and partial restoration of water bodies of the hydrographic system of the Agrakhan Bay. Clearing silted and overgrown channels, deepening and collapsing of preserved reservoirs, directing the necessary volumes of river water to the Northern and Southern Agrakhan (in accordance with the calculated supply schedule), will reduce overgrowth and siltation of water bodies, restore water exchange between them, improve water quality, revive the fisheries of the region, improve the habitat conditions of many rare and protected animal species, increase the recreational attractiveness of the region.

Keywords: Agrakhan Bay, Caspian Sea, fisheries, degradation of the bay, water quality, ecological condition, ecological rehabilitation, spawning-growing reservoirs, rare species, hydrological modeling.

Financing. The collection and analysis of materials was carried out under a state contract with the West Caspian STB No. NIR-18-01. The preparation of the article was carried out within the framework of the research of the Department of Land Hydrology of the Geographical Faculty of Lomonosov Moscow State University, carried out within the framework of the state task (CITIS number: 121051400038-1).

DOI: 10.24412/1993-3916-2022-4-163-178

EDN: IBMCGO