Effects of deposition of deer dung on nutrient redistribution and on soil and plant nutrients on intensively grazed grasslands in lowland Nepal

Nutrient redistribution, deer response to areas containing dung, and plant and soil nutrient content on grazing lawns and adjacent control areas were studied on intensively grazed grasslands in humid lowland Nepal. Effects of experimental fertilisation of grasslands with different amounts of dung pellets were also studied. A high-density population of axis deer recirculated 13 tons (dry mass, DM) of dung per month in the 10 km² study area. Because of preferential use of the grasslands for feeding while resting elsewhere, 10 tons were lost from the grassland to other habitat types per month during the dry season (February–May). The N, P, K, Na, and Mg content of grass from grazing lawns was significantly higher, probably because the grass was kept in a younger phenological stage of growth. In contrast with results from many other studies, the nutrient content of lawn soil was similar to that of adjacent, less intensively grazed areas, apart from P, which was lower in lawn soils. High plant P requirement on grazing lawns and removal of nutrients by deer may explain low soil P levels. Experiments with pellet fertilisation showed that high dung deposition increased plant P content, probably because of increased P uptake during early stages of growth. Dung deposition did not affect deer grazing preferences.