Effect of Keeping Animals in Zoo Enclosures on Changes in Physical Properties of Soils

Abstract

Zoos are pretty popular places in any city on our planet. Having a research base, zoos consider the main goal to study the possibility of reproduction and conservation of animal species from the point of view of their physiology without considering essential components of the animal environment, such as soil. This study aimed to monitor changes in the physical properties of soils disturbed by the influence of animals in the enclosures of the Rostov Zoo, Russia. Enclosures with ungulates, birds, and recreational and park areas not exposed to animals were selected. To assess the ecological state of the soil, the load of animals in enclosures, hoof pressure on the soil, and changes in bulk density, penetration resistance, soil structure, soil moisture, and soil temperature were determined. Over-compaction of the soil cover and deterioration of the soil structure in the enclosures were revealed in comparison with the control section of the zoo’s park zone without animals. The soil penetration resistance deteriorated significantly in the enclosures’ 0-10 cm surface layer. A gradual decline was noted below in the profile. This is due to the strong influence of the mechanical load of animals, mainly on the surface of the soil cover. The change in soil temperature and soil moisture was seasonal. Animals in a limited area subject the vegetation and soil cover of the enclosures to complete trampling and over-compaction that worsens the ecological condition in this area.